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Foseco Non-Ferrous Foundryman’s Handbook



Foseco Non-Ferrous
Foundryman’s Handbook
Eleventh edition

Revised and edited by
John R. Brown

OXFORD

AUCKLAND

BOSTON

JOHANNESBURG

MELBOURNE

NEW DELHI


Preface

The last edition of the Handbook was published in 1994 and like all the earlier
editions, it aimed to provide a practical reference book for all those involved
in making castings in any of the commonly used alloys by any of the usual
moulding methods. In order to keep the Handbook to a reasonable size, it was
not possible to deal with all the common casting alloys in detail. Since 1994

the technology of casting has continued to develop and has become more
specialised so that it has been decided to publish the 11th edition of the
Handbook in three separate volumes:
Non-ferrous
Iron
Steel

dealing with aluminium, copper and magnesium casting
alloys
dealing with grey, ductile and special purpose cast
irons
dealing with carbon, low alloy and high alloy steels

Certain chapters (with slight modifications) are common to all three
volumes: these chapters include tables and general data, sands and sand
bonding systems, resin bonded sand, sodium silicate bonded sand and
feeding systems. The remaining chapters have been written specifically for
each volume.
The Handbook refers to many Foseco products. Not all of the products are
available in every country and in a few cases, product names may vary.
Users should always contact their local Foseco company to check whether a
particular product or its equivalent is available.
The Foseco logo and all product names appearing in capital letters are
trademarks of the Foseco group of companies, used under licence.
John R. Brown


................................... Preface
...................................................
Acknowledgements

1 Tables and general data .........................................

1

SI units and their relation to other units ...................................
SI, metric, non-SI and non-metric conversions........................
Conversion table of stress values............................................
Areas and volumes of circles, spheres, cylinders etc. .............
The physical properties of metals............................................
The physical properties of metals (Continued) ........................
Densities of casting alloys .......................................................
Approximate bulk densities of common materials ...................
Patternmakers contraction allowances ...................................
Volume shrinkage of principal casting alloys ...........................
Comparison of sieve sizes.......................................................
Calculation of average grain size ............................................
Calculation of AFS grain fineness number ..............................
Recommended standard colours for patterns .........................
Dust control in foundries..........................................................
Buoyancy forces on cores .......................................................
Core print support....................................................................
Opening forces on moulds.......................................................
Dimensional tolerances and consistency achieved in
castings ...................................................................................

1
2
5
6
7

8
9
10
11
13
14
15
16
17
18
18
19
19
21

...................................... alloys
2 Aluminium casting

.....................................................
Introduction
Casting alloys ..........................................................................
Casting processes ...................................................................
The effect of alloying elements................................................
Heat treatment of aluminium alloys .........................................

25
39
39
42

....................................... alloys
3 Melting aluminium

.....................................................
Introduction
Raw materials..........................................................................
Melting furnaces ......................................................................
Corundum growth ....................................................................
Choice of melting unit ..............................................................

47
47
54
55


..................................... Fluxes
4
Application of COVERAL powder fluxes
..................................
Granular COVERAL fluxes ......................................................

61

5 INSURAL refractory for ladles and metal
......................................
transport
Ladle liners ..............................................................................

65

6 Treatment of aluminium alloy melts
.....................
Hydrogen gas pick-up in aluminium melts
...............................
Degassing aluminium alloys ....................................................
Grain refinement of aluminium alloys ......................................
Modification of aluminium alloys..............................................
Sodium modification ................................................................
Strontium modification .............................................................
Permanent modification ...........................................................
Sand, gravity die and low pressure diecasting ........................
Medium silicon alloys, 4 7% Si ................................................
Eutectic silicon alloys, 12% Si .................................................
Treatment of hypereutectic Al Si alloys (over 16% Si) ...........
Melting and treatment of aluminium magnesium alloys (
4 10% Mg) ..............................................................................
Special requirements for gravity diecasting .............................
Treatment of alloys for pressure diecasting.............................

7 Running, gating and feeding aluminium
castings ......................................................................
Gating without filters ................................................................
Gating with filters .....................................................................
Feeding mechanisms in Al alloy and other non- ferrous
castings ...................................................................................
Simulation modelling ...............................................................

72
77

79
81
82
83
83
84
84
85
86
87
87

75
90
93
94
98

8 Filtration of aluminium alloy castings
..................
SIVEX FC filters.......................................................................
Use of filters in conventional running systems ........................
Direct pouring of aluminium alloy castings ..............................
KALPUR combined sleeve and SIVEX FC filter for
aluminium castings ..................................................................
Direct pouring into metal dies ..................................................

100
101
104

105
107


9 Pressure diecasting of aluminium alloys
.............

...................................................
Die design
Process control........................................................................
Modification of the diecasting process.....................................
Applications of diecastings ......................................................
The diecasting foundry ............................................................
Die coating...............................................................................

111
113
114
114
116

10 Low pressure and gravity diecasting
.................
..........................................................diecasting
Low pressure
Gravity diecasting ....................................................................
Die coatings for gravity and low pressure diecasting ..............

124
127

.......................................
11 Sand casting processes
Green sand..............................................................................
Moulding machines..................................................................
Core assembly sand processes ..............................................
The Lost Foam process ...........................................................

136
137
140
144

12 Sands and sand bonding systems
......................
Properties of silica sand for foundry use
.................................
Typical silica foundry sand properties .....................................
Safe handling of silica sand .....................................................
Segregation of sand ................................................................
Measurement of sand properties .............................................
Thermal characteristics of silica sand......................................
Zircon, ZrSiO4 .........................................................................
Chromite, FeCr2O4 .................................................................
Olivine, Mg2SiO4.....................................................................
Green sand additives...............................................................
The green sand system ...........................................................
Green sand properties .............................................................
Control of green sand systems................................................
Sand testing.............................................................................

Control graphs .........................................................................
Parting agents .........................................................................
Special moulding materials, LUTRON .....................................

............................................... sand
13 Resin bonded

151
152
153
153
153
154
156
156
157
160
163
164
165
165
166
166


.........................................................
Chemically bonded sand
Self-hardening process (also known as self-set, no- bake
.......................................................... process)
or cold- setting

Testing chemically bonded, self-hardening sands...................
Mixers ......................................................................................
Sand quality .............................................................................
Pattern equipment ...................................................................
Curing temperature..................................................................
Design of moulds using self-hardening sand...........................
Foundry layout .........................................................................
Sand reclamation.....................................................................
Typical usage of sand reclamation ..........................................
Furanes ...................................................................................
Phenolic-isocyanates (phenolic-urethanes).............................
Alkaline phenolic resin, ester hardened...................................
Heat triggered processes ........................................................
Gas triggered systems.............................................................
The shell or Croning process...................................................
Hot-box process ......................................................................
Warm-box process ..................................................................
Oil sand ...................................................................................
Phenolic-urethane-amine gassed (cold-box) process .............
ECOLOTEC process (alkaline phenolic resin gassed with
CO2) ........................................................................................
The SO2 process.....................................................................
SO2- cured epoxy resin ...........................................................
Ester-cured alkaline phenolic system ......................................
Review of resin core-making processes..................................

169
171
172
172

173
173
173
175
178
180
182
183
185
186
187
189
190
191
193
195
196
198
198
199

14 Sodium silicate bonded sand
..............................

........................................................... silicate
Sodium
CO2 silicate process ( basic process) .....................................
Gassing CO2 cores and moulds..............................................
Improvements to the CO2 silicate process..............................
The CARSIL range of silicate binders .....................................

SOLOSIL .................................................................................
Self-setting sodium silicate processes.....................................
Ester silicate process...............................................................
Adhesives and sealants...........................................................
CORSEAL sealants .................................................................

205
207
208
209
209
210
210
215
215


TAK sealant .............................................................................

215

.............................................. casting
15 Magnesium

.........................................................
Casting alloys
The melting, treatment and casting of magnesium alloys .......

218

16 Copper and copper alloy castings
......................
The main copper alloys and their applications
........................
Specifications for copper-based alloys ....................................
Colour code for ingots .............................................................
Melting copper and copper-based alloys .................................
Melting and treatment of high conductivity copper ..................
Copper-silver ...........................................................................
Copper cadmium ....................................................................
Copper chromium ...................................................................
Commercial copper .................................................................
Melting and treatment of brasses, copper zinc alloys.............
Melting bronzes and gunmetals...............................................
Melting aluminium bronze........................................................
Melting manganese bronze .....................................................
Melting high lead bronze .........................................................
Melting copper nickel alloys....................................................
Filtration of copper-based alloys..............................................

226
227
232
238
242
243
243
243
244
248

250
250
250
251
251

...................................................
17 Feeding systems

........................................................... feeders
Natural
Aided feeders ..........................................................................
Feeding systems .....................................................................
The calculation of feeder dimensions ......................................
Steel, malleable iron, white irons, light alloys and copperbased alloy castings ................................................................
Grey and ductile irons..............................................................
Introduction..............................................................................
Range of feeder products ........................................................
Breaker cores ..........................................................................
The application of feeder sleeves............................................
Williams Cores.........................................................................
FERRUX anti-piping compounds for iron and steel
castings ...................................................................................
Metal-producing top surface covers ........................................
FEEDOL anti-piping compounds for all non-ferrous alloys......

253
254
257
262

266
268
269
279
280
283
284
285
286


................................

Aids ot the calculation of FEEDER requirements ....................
Nomograms .............................................................................
FEEDERCALC ........................................................................
Calculating feeder sizes for aluminium alloy castings .............

Index

286
287
287
288


Acknowledgements

The following Organisations have generously permitted the use of their
material in the Handbook:

The American Foundrymen’s Society, Inc., 505 State Street, Des Plaines,
Illinois 60016-8399, USA.
The Association of Light Alloy Founders (ALARS), Broadway House,
Calthorpe Road, Five Ways, Birmingham, B15 1TN.
BSI, Extracts from British Standards are reproduced with the permission of
British Standards Institution. Complete copies can be obtained by post
from Customer Services, BSI, 389 Chiswick High Road, London W4
4AL.
Buhler UK Ltd, 19 Station Road, New Barnet, Herts, EN5 1NN.
Butterworth-Heinemann, Linacre House, Jordan Hill, Oxford OX2 8DP.
The Castings Development Centre (incorporating BCIRA), Bordesley Hall,
The Holloway, Alvechurch, Birmingham, B48 7QB.
The Castings Development Centre (incorporating Steel Castings Research &
Trade Association), 7 East Bank Road, Sheffield, S2 3PT.
Chem-Trend (UK) Ltd, Bromley Street, Lye, Stourbridge, West Midlands
DY9 8HY.
Copper Development Association, Verulam Industrial Estate, 224, London
Road, St. Albans, Herts, AL1 1AQ.
Foundry International, DMG Business Media Ltd, Queensway House, 2
Queensway, Redhill, Surrey, RH1 1QS.
Foundry Management & Technology, 1100 Superior Avenue, Cleveland, OH
44114, USA.
Foundry & Technical Liaison Ltd, 6-11 Riley Street, Willenhall, West
Midlands, WV13 1RH.
The Institute of British Foundrymen, Bordesley Hall, The Holloway,
Alvechurch, Birmingham,
B48 7QA.
International Magnesium Association, 1303 Vincent Place, Suite One,
McLean, Virginia 22101, USA.
OEA (Organisation of European Aluminium Refiners and Remelters,

Broadway House, Calthorpe Road, Five Ways, Birmingham, B15 1TN.
Ramsell Furnaces Ltd, Wassage Way, Hampton Lovett Industrial Estate,
Droitwich, Worcestershire, WR9 0NX.
Striko UK Ltd, Newcastle Street, Stone, Staffordshire, ST15 8JT.
The author gratefully acknowledges the help received from many individuals, in particular from colleagues at Foseco.


Acknowledgements

xiii

All statements, information and data contained herein are published as
a guide and although believed to be accurate and reliable (having
regard to the manufacturer’s practical experience) neither the manufacturer, licensor, seller nor publisher represents or warrants, expressly
or implied:
1 Their accuracy/reliability
2 The use of the product(s) will not infringe third party rights
3 No further safety measures are required to meet local
legislation.
The seller is not authorised to make representations nor contract on
behalf of the manufacturer/licensor. All sales by the manufacturer/
seller are based on their respective conditions of sale available on
request.



Chapter 1

Tables and general data

SI units and their relation to other units
The International System of Units (SI System) is based on six primary
units:
Quantity

Unit

Symbol

length
mass
time
electric current
temperature
luminous intensity

metre
kilogram
second
ampere
degree Kelvin
candela

m
kg
s
A
K
cd

Multiples
SI prefixes are used to indicate multiples and submultiples such as 106 or
10–3
Prefix
10
102
103
106
109
1012

Symbol

deca
hecto
kilo
mega
giga
tera

da
h
k
M
G
T

Prefix
10–1
10–2

10–3
10–6
10–9
10–12

Symbol

deci
centi
milli
micro
nano
pico

d
c
m
␮
n
p

Example: One millionth of a metre is expressed as one micrometre, 1 ␮m.


2

Foseco Non-Ferrous Foundryman’s Handbook

Derived units
The most important derived units for the foundryman are:

Quantity

Unit

Symbol

Force
Pressure, stress
Work, energy
Power, heat flow rate
Temperature
Heat flow rate
Thermal conductivity
Specific heat capacity
Specific latent heat

newton
newton per square metre or pascal
joule
watt, joule per second
degree Celsius
watt per square metre
watt per metre degree
joule per kilogram degree
joule per kilogram

N (kg m/s2 )
N/m2 (Pa)
J (Nm)
W (J/s)

°C
W/m2
W/m K
J/kg K
J/kg

SI, metric, non-SI and non-metric conversions
Length:
1 in
=
1 ft
=
1m
=
1 km =
1 mile =
1 yd =

25.4 mm
0.3048 m
1.09361 yd
1093.61 yd = 0.621371 miles
1.60934 km = 1760 yd
0.9144 m

Area:
1 in2
1 ft2
1 m2
1 mm2

1 yd2
1 acre
1 hectare

=
=
=
=
=
=
=

Volume:
1 cm3
1 dm3
1 ft3
1 gal (imp)
1 in3
1 l (litre)
1 m3

654.16 mm2
0.092903 m2
1.19599 yd2 = 10.76391 ft2
0.00155 in2
0.836127 m2
4840 yd2 = 4046.86 m2 = 0.404686 m2 hectare
2.47105 acre = 10 000 m2

=

=
=
=
=
=
=

0.061024 in3
1 l (litre) = 0.035315 ft3
0.028317 m3 = 6.22883 gal (imp)
4.54609 l (litre)
16.3871 cm3
1 dm3 = 0.001 m3 = 0.21997 gal (imp)
1.30795 yd3 = 35.31467 ft3


Tables and general data

1 pt (pint)
1 US gal
1 ft3/min (cfm)
1 ft3/sec

=
=
=
=

Mass:
1 lb (pound)

1 cwt
1 kg
1 oz
1 ton
1 ton (US)

3

0.453592 kg
50.802 kg
2.20462 lb
28.349 gm
2240 lb = 1.01605 t (tonne) = 1016.05 kg
2000 lb = 907.185 kg

=
=
=
=
=
=

0.568261 l
3.78541 l = 0.832674 gal (imp)
1.699 m3/h
28.3168 l/s

Force:
1 kgf
= 9.80665 N = 2.20462 lbf = 1 kp (kilopond)

1 lbf
= 4.44822 N
1 pdl (poundal) = 0.138255 N
Density:
1 kgf/m3 = 0.062428 lb/ft3
1 lb/ft3 = 16.0185 kg/m3
1 g/cm3 = 1000 kg/m3
Pressure, stress:
1 kgf/cm2
1 kgf/mm2
1 lbf/in2 (psi)
1 Pa (N/m2 )
1 in w.g. (in H2O)
1 N/mm2

=
=
=
=
=
=

98.0665 kPa (kN/m2 )
9.80665 N/mm2 = 1422.33 lbf/in2 = 0.63497 tonf/in2
6.89476 kPa (kN/m2 )
0.000145038 lbf/in2
249.089 Pa
1 MPa = 145.038 lbf/in2 = 0.06475 tonf/in2
= 0.10197 kgf/cm2

Power:
1 kW
= 3412 Btu/hr
1 hp (horsepower) = 0.745700 kW
Energy, heat, work:
1 Btu
= 1.05506 kJ
1 cal
= 4.1868 J
1 kWh = 3.6 MJ = 3412 Btu
1 therm = 100 000 Btu = 105.506 MJ
1 kJ
= 0.277778 W.h
Specific heat capacity, heat transfer:
1 cal/g°C
= 1 kcal/kg°C = 4186.8 J/kg.K
1 Btu/lb°F
= 4186.8 J/kg.K
1 Btu/h
= 0.293071 W


4

Foseco Non-Ferrous Foundryman’s Handbook

1 cal/cm.s°C = 418.68 W/m.K (thermal conductivity)
1 Btu.in/ft2h°F = 0.144228 W/m.K (thermal conductivity)
= 5.67826 W/m2.K (heat transfer coeff.)
1 Btu/ft2h°F

Miscellaneous:
1 std.atmos.
1 bar
1 cP (centipoise)
1 cSt (centistoke)
1 cycle/s
1 hp

=
=
=
=
=
=

101.325 kPa = 760 mm Hg = 1.01325 bar
100 kPa = 14.5038 lbf/in2
1 mPa.s
1 mm2/s
1 Hz (Hertz)
745.7 W

Useful approximations:
1 Btu
= 1 kJ
1 kg
1 ft
= 30 cm
1 kgf
1 gal

= 41⁄2 l
1 std atmos.
1 ha
= 21⁄2 acre
1 km
1 hp
= 3⁄4 kW
1 litre
1 in
= 25 mm
1 lbf
1 therm
= 100 MJ
1 yd
= 15 N/mm2
1 tonf/in2
1 psi (lbf/in2 ) = 7 kPa
1 N (newton) = the weight of a small apple!
Temperature:
°F
= 1.8 ϫ °C + 32
°C
= (°F – 32)/1.8
0°C (Celsius) = 273.15 K (Kelvin)

=
=
=
=
=

=
=

21⁄4 lb
10 N
1 bar
5
⁄8 mile
13⁄4 pint
41⁄2 N
0.9 m


Tables and general data

5

Conversion table of stress values
Equivalent stresses
American
(lb/in2 )

British
(ton/in2 )

Metric
(kgf/mm2 )

SI
(N/mm2 )

250
500

0.112
0.223

0.176
0.352

1.724
3.447

1000
2000
3000
4000
5000

0.446
0.893
1.339
1.788
2.232

0.703
1.406
2.109
2.812
3.515

6.895
13.789
20.684
27.579
34.474

10 000
15 000
20 000
25 000
30 000

4.464
6.696
8.929
11.161
13.393

7.031
10.546
14.062
17.577
21.092

68.947
103.421
137.894
172.368
206.841

35 000
40 000
45 000
50 000
55 000

15.652
17.875
20.089
22.321
24.554

24.608
28.123
31.639
35.154
38.670

241.315
275.788
310.262
344.735
379.209

60 000
65 000
70 000
75 000
80 000

26.786
29.018
31.250
33.482
35.714

42.185
45.700
49.216
52.731
56.247

413.682
448.156
482.629
517.103
551.576

85 000
90 000
95 000
100 000

37.946
40.179
42.411
44.643

59.762

63.277
66.793
70.308

586.050
620.523
654.997
689.470

Conversions
10 000
22 399
14 223
14 504

4.464
10
6.349
6.475

7.031
15.749
10
10.197

68.947
154.438
98.066
100

6

Foseco Non-Ferrous Foundryman’s Handbook

Areas and volumes of circles, spheres, cylinders etc.
␲ = 3.14159 (approximation: 22/7)
1 radian = 57.296 degrees
Circle; radius r, diameter d:
circumference = 2␲r = ␲d
area = ␲r 2 = ␲/4 ϫ d 2
Sphere; radius r:
surface area = 4␲r 2
volume = 4⁄3 ␲r 3
Cylinder; radius of base r, height h:
area of curved surface = 2␲rh
volume = ␲r 2h
Cone; radius of base r, height h:
volume = 1⁄2 area of base ϫ height
= 1⁄2␲r 2h
Triangle; base b, height h:
area = 1⁄2bh


Tables and general data

7

The physical properties of metals

Aluminium
Antimony
Arsenic
Barium
Beryllium
Bismuth
Cadmium
Calcium
Carbon
Cerium
Chromium
Cobalt
Copper
Gallium
Gold
Indium
Iridium
Iron
Lead
Lithium
Magnesium
Manganese
Mercury
Molybdenum
Nickel
Niobium
Osmium
Palladium
Phosphorus
Platinum

Potassium
Rhodium
Silicon
Silver
Sodium
Strontium
Sulphur
Tantalum
Tellurium
Thallium
Tin
Titanium
Tungsten
Uranium
Vanadium
Zinc
Zirconium

Symbol

Al
Sb
As
Ba
Be
Bi
Cd
Ca
C
Ce

Cr
Co
Cu
Ga
Au
In
Ir
Fe
Pb
Li
Mg
Mn
Hg
Mo
Ni
Nb
Os
Pd
P
Pt
K
Rh
Si
Ag
Na
Sr
S
Ta
Te
Tl

Sn
Ti
W
U
V
Zn
Zr

Atomic
weight

26.97
121.76
74.93
137.37
9.02
209.0
112.41
40.08
12.01
140.13
52.01
58.94
63.57
69.74
197.2
114.8
193.1
55.84
207.22

6.94
24.32
54.93
200.61
96.0
58.69
92.91
190.9
106.7
31.04
195.23
39.1
102.91
28.3
107.88
23.00
87.63
32.0
180.8
127.6
204
118.7
47.9
184.0
238.2
50.95
65.38
90.6

Melting

point
(°C)

660.4
630.7
volat·
729
1287
271.4
321.1
839
–
798
1860
1494
1085
29.7
1064.4
156
2447
1536
327.5
181
649
1244
–38.9
2615
1455
2467
3030

1554
44.1
1770
63.2
1966
1412
961.9
97.8
770
115
2980
450
304
232
1667
3387
1132
1902
419.6
1852

Boiling
point
(°C)

2520
1590
616
2130
2470

1564
767
1484
–
3430
2680
2930
2560
2205
2860
2070
4390
2860
1750
1342
1090
2060
357
4610
2915
4740
5000
2960
279
3830
759
3700
3270
2163
883

1375
444.5
5370
988
1473
2625
3285
5555
4400
3410
911
4400

Latent heat of
fusion

Mean specific heat
0–100°C

(kJ/kg) (cal/g)

Element

(kJ/kg·K) (cal/g°C)

386.8
101.7
–
–
133.5

54.4
58.6
328.6
–
–
132.7
244.5
180.0
80.2
67.4
–
–
200.5
20.9
137.4
194.7
152.8
12.6
–
305.6
–
–
150.7
20.9
113.0
67.0
–
502.4
92.1
115.1

–
32.7
154.9
31.0
–
61.1
376.8
167.5
–
334.9
110.1
–

92.4
24.3
–
–
31.9
13.0
14.0
78.5
–
–
31.7
58.4
43.0
19.2
16.1
–
–

47.9
5.0
32.8
46.5
36.5
3.0
–
73.0
–
–
36.0
5.0
27.0
16.0
–
120.0
22.0
27.5
–
9.0
37.0
7.4
–
14.6
90.0
40.0
–
80.0
26.3
–

0.917
0.209
0.331
0.285
2.052
0.125
0.233
0.624
0.703
0.188
0.461
0.427
0.386
0.377
0.130
0.243
0.131
0.456
0.130
3.517
1.038
0.486
0.138
0.251
0.452
0.268
0.130
0.247
0.791

0.134
0.754
0.243
0.729
0.234
1.227
0.737
0.068
0.142
0.134
0.130
0.226
0.528
0.138
0.117
0.498
0.394
0.289

0.219
0.050
0.079
0.068
0.490
0.030
0.056
0.149
0.168
0.045
0.110

0.102
0.092
0.090
0.031
0.058
0.031
0.109
0.031
0.840
0.248
0.116
0.033
0.060
0.108
0.064
0.031
0.059
0.189
0.032
0.180
0.058
0.174
0.055
0.293
0.176
0.016
0.034
0.032
0.031
0.054

0.126
0.033
0.029
0.119
0.094
0.069


8

Foseco Non-Ferrous Foundryman’s Handbook

The physical properties of metals (Continued)
Element

Al
Sb
As
Ba
Be
Bi
Cd
Ca
C
Ce
Cr
Co
Cu
Ga
Au

In
Ir
Fe
Pb
Li
Mg
Mn
Hg
Mo
Ni
Nb
Os
Pd
P
Pt
K
Rh
Si
Ag
Na
Sr
S
Ta
Te
Tl
Sn
Ti
W
U
V

Zn
Zr

Thermal
conductivity
(W/m·K)

Resistivity
(␮ohm·cm
at 20°C)

Vol· change
on melting
(%)

Density
(g/cm3 )

Coeff· of
expansion
(ϫ 10–6/K)

Brinell
hardness
no·

238
23.8
–
–

194
9
103
125
16.3
11.9
91.3
96
397
41
316
80
147
78
35
76
156
7.8
8.7
137
89
54
87
75
–
73
104
148
139
425

128
–
272
58
3.8
45.5
73.2
21.6
174
28
31.6
120
22.6

2.67
40.1
33.3
60
3.3
117
7.3
3.7
–
85.4
13.2
6.3
1.69
–
2.2
8.8

5.1
10.1
20.6
9.3
4.2
160
96
5.7
6.9
16
8.8
10.8
–
10.6
6.8
4.7
103 –106
1.6
4.7
23
–
13.5
1·6 ϫ 105
16.6
12.6
54
5.4
27
19.6
6.0

44

6.6
1.4
–
–
–
–3.3
4.7
–
–
–
–
–
4.1
–
5.2
–
–
5.5
3.4
1.5
4.2
–
3.75
–
–
–
–
–

–
–
2.8
–
–
4.5
2.5
–
–
–
–
–
2.8
–
–
–
–
6.5
–

2.70
6.68
5.73
3.5
1.85
9.80
8.64
1.54
2.30
6.75

7.10
8.90
8.96
5.91
19.3
7.3
22.4
7.87
11.68
0.53
1.74
7.4
13.55
10.2
8.9
8.6
22.5
12.0
1.83
21.45
0.86
12.4
2.34
10.5
0.97
2.6
2.07
16.6
6.24
11.85

7.3
4.5
19.3
19.0
6.1
7.14
6.49

23.5
11
5.6
18
12
13.4
31
22
7.9
8
6.5
12.5
17
18.3
14.1
24.8
6.8
12.1
29
56
26
23

61
5.1
13.3
7.2
4.6
11.0
6.2
9.0
83
8.5
7.6
19.1
71
100
70
6.5
–
30
23.5
8.9
4.5
–
8.3
31
5.9

17
30
–
–

–
9
20
13
–
–
350
125
48
–
18.5
1
172
66
5.5
–
25
–
–
147
80
–
–
50
–
52
0.04
156
–
25

0.1
–
–
40
–
–
–
–
–
–
–
35
–


Tables and general data

9

Densities of casting alloys
Alloy
Aluminium alloys
Pure Al
Al–Si5Cu3
Al–Si7Mg
Al–Si8Cu3Fe
AlSi12

BS1490 g/ml

LM4
LM25
LM24
LM6

2.70
2.75
2.68
2.79
2.65

Cast steels
Low carbon <0.20
Med. carbon 0.40
High carbon >0.40

7.86
7.86
7.84

Low alloy
Med. alloy
Med./high alloy

7.86
7.78
7.67

Stainless
13Cr

18Cr8Ni

7.61
7.75

Other alloys
Zinc base
ZnAl4Cu1

6.70

Lead base
PbSb6
Tin base (Babbit)
Inconel Ni76Cr18

10.88
7.34
8.50

Alloy
Copper alloys
HC copper
Brass CuZn38Al
CuZn33Pb2Si
CuZn33Pb2
Phosphor bronze
CuSn11P
CuSn12
Lead bronze

CuSn5Pb20
Al bronze
CuAl10Fe2
Gunmetal
CuSnPb5Zn5
Copper nickel
CuNi30Cr2FeMnSi
Cast irons
Grey iron 150 MPa
200
250
300
Whiteheart malleable
Blackheart malleable
White iron
Ductile iron (s.g.)
Ni-hard
High silicon (15%)

BS1400 g/ml

HCC1
DCB1
HTB1
SCB3

8.9
8.5
8.5
8.5

PB1
PB2

8.8
8.7

LB5

9.3

AB1

7.5

LG2

8.8

CN1

8.8

6.8–7.1
7.0–7.2
7.2–7.4
7.3–7.4
7.45
7.27
7.70

7.2–7.3
7.6–7.7
6.8


10 Foseco Non-Ferrous Foundryman’s Handbook

Approximate bulk densities of common materials
kg/m3

lb/ft3

2560
2675
7610
590

160
167
475
37

Brass, rolled
swarf
Babbit metal
Brick, common
fireclay
Bronze

8390

2500
7270
1360–1890
1840
8550

524
157
454
85–118
115
534

Cast iron, solid
turnings
Cement, loose
Chalk
Charcoal, lump
Clay
Coal
Coal dust
Coke
Concrete
Copper, cast
Cupola slag

7210
450
2240
140

1360
85
2240
140
290
18
1900–2200 120–135
960–1280
60–80
850
53
450
28
2240
140
8780
548
2400
150

Material
Aluminium, cast
wrought
Aluminium bronze
Ashes

Dolomite

2680

167

Fire clay
French chalk

1440
2600

90
162

2230
19 200
17 500
480
2200

139
1200
1090
30
138

Glass
Gold, pure
22 carat
Graphite, powder
solid

kg/m3

Material
Lead
Limestone

lb/ft3

11370
710
2530–2700 158–168

Magnesite
Mercury
Monel

2530
13 560
8870

158
847
554

Nickel, cast
Nickel silver

8270
8270

516

516

Phosphor bronze
Pig iron, mean
Pig iron and scrap
(cupola charge)

8580
4800

536
300

5400

336

Sand, moulding
silica
Silver, cast
Steel
Tin
Water, ice
liquid
Wood, balsa
oak
pine
teak
Wrought iron
Zinc, cast

rolled

1200–1440
1360–1440
10500
7850
7260

0°C
100°C

940
1000
955
100–130
830
480
640
7700
6860
7180

75–90
85–90
656
490
453
58.7
62.4
59.6

7–8
52
30
40
480
428
448


Tables and general data

11

Patternmakers’ contraction allowances
Castings are always smaller in dimensions than the pattern from which they
are made, because as the metal cools from its solidification temperature to
room temperature, thermal contraction occurs. Patternmakers allow for this
contraction by making patterns larger in dimensions than the required
castings by an amount known as the “contraction allowance”. Originally
this was done by making use of specially engraved rules, known as
“contraction rules”, the dimensions of which incorporated a contraction
allowance such as 1 in 75 for aluminium alloys, or 1 in 96 for iron castings.
Nowadays, most patterns and coreboxes are made using computercontrolled machine tools and it is more convenient to express the contraction
as a percentage allowance.
Predicting casting contraction can never be precise, since many factors are
involved in determining the exact amount of contraction that occurs. For
example, when iron castings are made in greensand moulds, the mould
walls may move under the pressure of the liquid metal, causing expansion
of the mould cavity, thus compensating for some of the metal contraction.
Cored castings may not contract as much as expected, because the presence

of a strong core may restrict movement of the casting as it is cooling. Some
core binders expand with the heat of the cast metal causing the casting to be
larger than otherwise expected. For these reasons, and others, it is only
possible to predict contractions approximately, but if a patternmaker works
with a particular foundry for a long period, he will gain experience with the
foundry’s design of castings and with the casting methods used in the
foundry. Based on such experience, more precise contraction allowances can
be built into the patterns.


12 Foseco Non-Ferrous Foundryman’s Handbook

The usually accepted contraction allowances for different alloys are given
in the following table.
Alloy

Contraction allowance (%)

Aluminium alloys
Al–Si5Cu3
LM4
Al–Si7Mg
LM25
Al–Si8Cu3Fe
LM24
Al–Si12
LM6

1.3

Beryllium copper
Bismuth
Brass
Bronze, aluminium
manganese
phosphor
silicon

1.6
1.3
1.56
2.32
0.83–1.56
1.0–1.6
1.3–1.6

Cast iron, grey
white
ductile (s.g.)
malleable

0.9–1.04
2.0
0.6–0.8
1.0–1.4

Copper
Gunmetal
Lead
Magnesium alloys

Monel

1.6
1.0–1.6
2.6
1.30–1.43
2.0

Nickel alloys
Steel, carbon
chromium
manganese
Tin

2.0
1.6–2.0
2.0
1.6–2.6
2.0

White metal
Zinc alloys

0.6
1.18