Zamak

thumb|Zamak ingots

ZAMAK (or Zamac, formerly trademarked as MAZAK) is an eclectic family of alloys with a base metal of zinc and alloying elements of aluminum, magnesium, and copper.

Zamak alloys are part of the zinc aluminum alloy family; they are distinguished from the other ZA alloys because of their constant 4% aluminum composition. These alloys are most commonly die-cast. Zamak avoided this by the use of 99.99% pure zinc metal, produced by New Jersey Zinc's use of a refluxer as part of the refining-process.

Zamak can be electroplated, wet-painted, and chromate-conversion-coated well.

Standards

Zinc alloy chemical composition standards are defined per country by the standard listed below:

{| class="wikitable"

|+ Zinc alloy standards per country

|-

! Country

! Zinc ingot

! Zinc casting

|-

| Europe

| EN1774

| EN12844

|-

| US

| ASTM B240

| ASTM B86

|-

| Japan

| JIS H2201

| JIS H5301

|-

| Australia

| AS 1881 - SAA H63

| AS 1881 - SAA H64

|-

| China

| GB 8738-88

| -

|-

| Canada

| CSA HZ3

| CSA HZ11

|-

| International

| ISO 301

| -

|}

Zamak goes by many different names based on standard and/or country:

{| class="wikitable"

|+ Various names for zamak alloys

|-

! Traditional name

! Short composition name

! Form

! Common

! ASTM^†

! Short European designation

! JIS

! China

! UK BS 1004

! France NFA 55-010 <br />or<br />Kirksite

| rowspan=2| ZnAl4Cu3

| rowspan=2| -

| ZX04

| ZX01

| -

| Z33520

|

| Ingot

| colspan=9| Used in Asia only

| ZA-4, ZN-004 It was originally designed for low volume sheet-metal-dies. It later gained popularity for making short-run injection-molding-dies.

|-

! Property

! Metric value

! Imperial value

|-

! colspan=3| Mechanical properties

|-

| Ultimate tensile strength

| 397 MPa (331 MPa aged)

| 58,000 psi

|-

| Yield strength (0.2% offset)

| 361 MPa

| 52,000 psi

|-

| Impact strength

| 38 J (7 J aged)

| 28&nbsp;ft-lbf (5&nbsp;ft-lbf aged)

|-

| Elongation at F_max

| colspan=2 align="center"| 3% (2% aged)

|-

| Elongation at fracture

| colspan=2 align="center"| 6%

|-

| Shear strength

| 317 MPa

| 46,000 psi

|-

| Compressive yield strength

| 641 MPa

| 93,000 psi

|-

| Fatigue strength (reverse bending 5 × 10⁸ cycles)

| 59 MPa

| 8,600 psi

|-

| Hardness

| colspan=2 align="center"| 130 Brinell (98 Brinell aged)

|-

| Modulus of elasticity

| 96 GPa

| 14,000,000 psi

|-

! colspan=3| Physical properties

|-

| Solidification range (melting range)

| 379–390&nbsp;°C

| 714–734&nbsp;°F

|-

| Density

| 6.8&nbsp;kg/dm³

| 0.25&nbsp;lb/in³

|-

| Coefficient of thermal expansion

| 27.8 μm/m-°C

| 15.4 μin/in-°F

|-

| Thermal conductivity

| 105 W/m-K

| 729 BTU-in/hr-ft²-°F

|-

| Electrical resistivity

| 6.85 μΩ-cm at 20°C

| 2.70 μΩ-in at 68&nbsp;°F

|-

| Latent heat (heat of fusion)

| 110 J/g

| 4.7 × 10⁻⁵ BTU/lb

|-

| Specific heat capacity

| 419 J/kg-°C

| 0.100 BTU/lb-°F

|-

| Coefficient of friction

| colspan=2 align="center"| 0.08

|}

KS

The KS alloy was developed for spin casting decorative parts. It has the same composition as zamak 2, except with more magnesium in order to produce finer grains and reduce the orange peel effect.

|-

! Property

! Metric value

! Imperial value

|-

! colspan=3| Mechanical properties

|-

| Ultimate tensile strength

| < 200MPa

| < 29,000psi

|-

| Yield strength (0.2% offset)

| < 200MPa

| < 29,000psi

|-

| Elongation

| colspan=2 align="center"| < 2%

|-

| Hardness

| colspan=2 align="center"| 150 Brinell max

|-

! colspan=3| Physical properties

|-

| Solidification range (melting range)

| 380-390°C

| 716-734°F

|-

| Density

| 6.6g/cm³

| 0.25lb/in³

|-

| Coefficient of thermal expansion

| 28.0μm/m-°C

| 15.4μin/in-°F

|-

| Thermal conductivity

| 105W/m-K

| 729BTU-in/hr-ft²-°F

|-

| Electrical conductivity

| colspan=2 align="center"| 25% IACS

|-

| Specific heat capacity

| 419J/kg-°C

| 0.100BTU/lb-°F

|-

| Coefficient of friction

| colspan=2 align="center"| 0.08

|}

Zamak 3

Zamak 3 is the de facto standard for the zamak series of zinc alloys; all other zinc alloys are compared to this. Zamak 3 has the base composition for the zamak alloys (96% zinc, 4% aluminum). It has excellent castability and long term dimensional stability. More than 70% of all North American zinc die castings are made from zamak 3. (Ingot)

| min

| 3.9

| -

| 0.025

| -

| -

| -

| -

| -

| -

| -

| -

|-

| max

| 4.3

| 0.1

| 0.05

| 0.004

| 0.003

| 0.002

| 0.035

| -

| -

| -

| -

|-

| rowspan=2|ASTM B86 (Cast)

| min

| 3.5

| -

| 0.025

| -

| -

| -

| -

| -

| -

| -

| -

|-

| max

| 4.3

| 0.25

| 0.05

| 0.005

| 0.004

| 0.003

| 0.1

| -

| -

| -

| -

|-

| rowspan=2|EN1774 (Ingot)

| min

| 3.8

| -

| 0.035

| -

| -

| -

| -

| -

| -

| -

| -

|-

| max

| 4.2

| 0.03

| 0.06

| 0.003

| 0.003

| 0.001

| 0.02

| 0.001

| 0.02

| -

| -

|-

| rowspan=2|EN12844 (Cast)

| min

| 3.7

| -

| 0.025

| -

| -

| -

| -

| -

| -

| -

| -

|-

| max

| 4.3

| 0.1

| 0.06

| 0.005

| 0.005

| 0.002

| 0.05

| 0.02

| 0.03

| -

| -

|-

| rowspan=2|JIS H2201

| min

| 3.9

| -

| 0.04

| -

| -

| -

| -

| -

| -

| -

| -

|-

| max

| 4.3

| 0.03

| 0.06

| 0.003

| 0.003

| 0.001

| 0.05

| -

| 0.001

| 0.0005

| 0.001

|-

| rowspan=2|GB8738-88

| min

| 3.9

| -

| 0.03

| -

| -

| -

| -

| -

| -

| -

| -

|-

| max

| 4.3

| 0.1

| 0.06

| 0.004

| 0.003

| 0.0015

| 0.035

| -

| -

| -

| -

|-

| colspan=13| ^†Impurity

|}

{| class="wikitable"

|+ Zamak 3 properties

|-

! Property

! Metric value

! Imperial value

|-

! colspan=3| Mechanical properties

|-

| Ultimate tensile strength

| 268 MPa

| 38,900 psi

|-

| Yield strength (0.2% offset)

| 208 MPa

| 30,200 psi

|-

| Impact strength

| 46 J (56 J aged)

| 34&nbsp;ft-lbf (41&nbsp;ft-lbf aged)

|-

| Elongation at F_max

| colspan=2 align="center"| 3%

|-

| Elongation at fracture

| colspan=2 align="center"| 6.3% (16% aged)

|-

| Shear strength

| 214 MPa

| 31,000 psi

|-

| Compressive yield strength

| 414 MPa

| 60,000 psi

|-

| Fatigue strength (reverse bending 5 × 10⁸ cycles)

| 48 MPa

| 7,000 psi

|-

| Hardness

| colspan=2 align="center"| 97 Brinell

|-

| Modulus of elasticity

| 96 GPa

| 14,000,000 psi

|-

! colspan=3| Physical properties

|-

| Solidification range (melting range)

| 381-387°C

| 718-729°F

|-

| Density

| 6.7g/cm³

| 0.24lb/in³

|-

| Coefficient of thermal expansion

| 27.4μm/m-°C

| 15.2μin/in-°F

|-

| Thermal conductivity

| 113W/mK

| 784BTU-in/hr-ft²-°F

|-

| Electrical resistivity

| 6.37μΩ-cm at 20°C

| 2.51μΩ-in at 68°F

|-

| Latent heat (heat of fusion)

| 110J/g

| 4.7 × 10⁻⁵ BTU/lb

|-

| Specific heat capacity

| 419J/kg-°C

| 0.100BTU/lb-°F

|-

| Coefficient of friction

| colspan=2 align="center"| 0.07

|}

Zamak 4

Zamak 4 was developed for the Asian markets to reduce the effects of die-soldering while maintaining the ductility of zamak 3. This was achieved by using half the amount of copper from the zamak 5 composition.

{| class="wikitable"

|+ Zamak 4 composition per standard

! colspan=2|

! colspan=3|Alloying elements

! colspan=8|Impurities

|-

! Standard

! Limit

! Al

! Cu

! Mg

! Pb

! Cd

! Sn

! Fe

! Ni

! Si

! In

! Tl

|-

| rowspan=2|Ningbo Jinyi Alloy Material Co.

| min

| 3.9

| 0.3

| 0.03

| -

| -

| -

| -

| -

| -

| -

| -

|-

| max

| 4.3

| 0.5

| 0.06

| 0.003

| 0.002

| 0.002

| 0.075

| -

| -

| -

| -

|}

{| class="wikitable"

|+ Zamak 4 properties

|-

! Property

! Metric value

! Imperial value

|-

! colspan=3| Mechanical properties

|-

| Ultimate tensile strength

| 317 MPa

| 46,000 psi

|-

| Yield strength (0.2% offset)

| 221-269 MPa

| 32,000-39,000 psi

|-

| Impact strength

| 61 J (7 J aged)

| 45ft-lbf (5ft-lbf aged)

|-

| Elongation

| colspan=2 align="center"| 7%

|-

| Shear strength

| 214-262 MPa

| 31,000-38,000 psi

|-

| Compressive yield strength

| 414-600 MPa

| 60,000-87,000 psi

|-

| Fatigue strength (rotary bending 5 × 10⁸ cycles)

| 48-57 MPa

| 7,000-8,300 psi

|-

| Hardness

| colspan=2 align="center"| 91 Brinell

|-

! colspan=3| Physical properties

|-

| Solidification range (melting range)

| 380-386°C

| 716-727°F

|-

| Density

| 6.6g/cm³

| 0.24lb/in³

|-

| Coefficient of thermal expansion

| 27.4 μm/m-°C

| 15.2 μin/in-°F

|-

| Thermal conductivity

| 108.9-113.0W/m-K @ 100&nbsp;°C

| 755.6-784.0 BTU-in/hr-ft²-°F @ 212°F

|-

| Electrical conductivity

| colspan=2 align="center"| 26-27% IACS

|-

| Specific heat capacity

| 418.7 J/kg-°C

| 0.100 BTU/lb-°F

|}

Zamak 5

Zamak 5 has the same composition as zamak 3 with the addition of 1% copper in order to increase strength (by approximately 10%

|-

! Property

! Metric value

! Imperial value

|-

! colspan=3| Mechanical properties

|-

| Ultimate tensile strength

| 331 MPa (270 MPa aged)

| 48,000 psi (39,000 psi aged)

|-

| Yield strength (0.2% offset)

| 295 MPa

| 43,000 psi

|-

| Impact strength

| 52 J (56 J aged)

| 38&nbsp;ft-lbf (41&nbsp;ft-lbf aged)

|-

| Elongation at F_max

| colspan=2 align="center"| 2%

|-

| Elongation at fracture

| colspan=2 align="center"| 3.6% (13% aged)

|-

| Shear strength

| 262 MPa

| 38,000 psi

|-

| Compressive yield strength

| 600 MPa

| 87,000 psi

|-

| Fatigue strength (reverse bending 5 × 10⁸ cycles)

| 57 MPa

| 8,300 psi

|-

| Hardness

| colspan=2 align="center"| 91 Brinell

|-

| Modulus of elasticity

| 96 GPa

| 14,000,000 psi

|-

! colspan=3| Physical properties

|-

| Solidification range (melting range)

| 380—386&nbsp;°C

| 716—727&nbsp;°F

|-

| Density

| 6.6&nbsp;kg/cm³

| 0.24&nbsp;lb/in³

|-

| Coefficient of thermal expansion

| 27.4 μm/m-°C

| 15.2 μin/in-°F

|-

| Thermal conductivity

| 109 W/mK

| 756 BTU-in/hr-ft²-°F

|-

| Electrical resistivity

| 6.54 μΩ-cm at 20&nbsp;°C

| 2.57 μΩ-in at 68&nbsp;°F

|-

| Latent heat (heat of fusion)

| 110 J/g

| 4.7 × 10⁻⁵ BTU/lb

|-

| Specific heat capacity

| 419 J/kg-°C

| 0.100 BTU/lb-°F

|-

| Coefficient of friction

| colspan=2 align="center"| 0.08

|}

Zamak 7

Zamak 7 has less magnesium than zamak 3 to increase fluidity and ductility, which is especially useful when casting thin wall components. In order to reduce inter-granular corrosion a small amount of nickel is added and impurities are more strictly controlled.

|-

! Property

! Metric value

! Imperial value

|-

! colspan=3| Mechanical properties

|-

| Ultimate tensile strength

| 285 MPa

| 41,300 psi

|-

| Yield strength (0.2% offset)

| 285 MPa

| 41,300 psi

|-

| Impact strength

| 58.0 J

| 42.8&nbsp;ft-lbf

|-

| Elongation at fracture

| colspan=2 align="center"| 14%

|-

| Shear strength

| 214 MPa

| 31,000 psi

|-

| Compressive yield strength

| 414 MPa

| 60,000 psi

|-

| Fatigue strength (reverse bending 5 × 10⁸ cycles)

| 47.0 MPa

| 6,820 psi

|-

| Hardness

| colspan=2 align="center"| 80 Brinell

|-

! colspan=3| Physical properties

|-

| Solidification range (melting range)

| 381—387&nbsp;°C

| 718—729&nbsp;°F

|-

| Coefficient of thermal expansion

| 27.4 μm/m-°C

| 15.2 μin/in-°F

|-

| Thermal conductivity

| 113 W/m-K

| 784 BTU-in/hr-ft²-°F

|-

| Electrical resistivity

| 6.4 μΩ-cm

| 2.5 μΩ-in

|-

| Specific heat capacity

| 419 J/kg-°C

| 0.100 BTU/lb-°F

|-

| Casting temperature

| 395—425&nbsp;°C

| 743—797&nbsp;°F

|}

Uses

Common uses for zamak alloys include appliances, bathroom fixtures, die cast toys and automotive industry. Zamak alloys are also used in the manufacture of some firearms such as those from Hi-Point Firearms. In World War 2, zamak alloy buttplates were one of three variations common on Canadian and American-made .303 Lee Enfield rifles, particularly during mid-war production.

See also

• Pot metal
• Babbitt (alloy)

References

External links

• Zinc Die Casting Alloy Guide