ASTM B860 : 13

Standard Specification for Zinc Master Alloys for Use in Hot Dip Galvanizing

Standard Details

1.1 This specification covers zinc master alloys which are used in hot dip galvanizing for the purpose of adjusting the concentration of certain alloying elements in the molten zinc bath. Table 1 covers the chemical composition of these materials which include six master alloys of zinc-aluminum (brightener) and one master alloy of zinc-antimony.

ASTM	Common		UNS
Type A-1	90/10 Zn/Al	High Purity	Z30750
Type A-2	90/10 Zn/Al	Low Purity	Z31710
Type A-3	95/5 Zn/Al	High Purity	Z30503
Type A-4	95/5 Zn/Al	Low Purity	Z31510
Type A-5	96/4 Zn/Al	High Purity	Z31520
Type A-6	96/4 Zn/Al	Low Purity	Z30504
Type S-1	90/10 Zn/Sb		Z55710

TABLE 1 Chemical Requirements Composition, % (Range or Maximum Value)^A

Type A-1	90 % Zinc–10 % Aluminum (90/10 Zn/Al)				High Purity
Type A-2	90 % Zinc–10 % Aluminum (90/10 Zn/Al)				Low Purity
Type A-3	95 % Zinc–5 % Aluminum (95/5 Zn/Al)				High Purity
Type A-4	95 % Zinc–5 % Aluminum (95/5 Zn/Al)				Low Purity
Type A-5	96 % Zinc–4 % Aluminum (96/4 Zn/Al)				High Purity
Type A-6	96 % Zinc–4 % Aluminum (96/4 Zn/Al)				Low Purity
Type S-1	90 % Zinc–10 % Antimony (90/10 Zn/Sb)
UNS^B	Type A-1 90/10 Zn/Al Z30750	Type A-2 90/10 Zn/Al Z31710	Type A-3 95/5 Zn/Al Z30503	Type A-4 95/5 Zn/Al Z31510	Type A-5 96/4 Zn/Al Z31520	Type A-6 96/4 Zn/Al Z30504	Type S-1 90/10 Zn/Sb Z55710
Fe	0.05 max	0.15 max	0.05 max	0.15 max	0.05 max	0.15 max	0.03 max
Pb	0.005 max	0.4 max	0.005 max	0.4 max	0.005 max†	0.4 max	0.015 max
Cd	0.004 max	...	0.004 max	...	0.004 max	...	0.003 max
Cu	0.035 max	0.5 max	0.035 max	0.5 max	0.035 max	0.5 max	0.003 max
Mg	...	...	...	...	0.06 max	0.06 max
Sn	0.003 max	...	0.003 max	...	0.003 max	...	0.01 max
As	...	...	...	...	...	...	0.015 max
Al	9.5–10.5	9.5–10.5	4.5–5.5	4.5–5.5	4.0-4.5	4.0-4.5	...
Sb^C	...	...	...	...	...	...	9.5–10.5
Others, Total	0.01 max	0.25 max	0.01 max	0.25 max	0.01 max	0.25 max	0.03 max
Zn^D	Remainder	Remainder	Remainder	Remainder	Remainder	Remainder	Remainder

^A The following applies to all specified limits in this table: For purposes of determining conformance with this specification, an observed value obtained from analysis shall be rounded off to the nearest unit in the last right-hand place of figures used in expressing the limiting value, in accordance with the rounding method of Practice E29.

^B UNS numbers in conformance with Practice E527.

^C Chemical method under development.

^D For information only. Quantitative determination of this element is not required. Zinc is assumed to be the difference between 100 % and the sum of those elements listed above.

† Corrected editorially.

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Material Safety Data Sheet (MSDS) for this product/material as provided by the manufacturer, to establish appropriate safety and health practices, and determine the applicability of regulatory limitations prior to use.

General Information

Status : Historical

Standard Type: Main

Document No: ASTM B860 : 13

Document Year: 2013

Pages: 3

Section Volume:
02.04 Volume 02.04 Nonferrous Metals - Nickel, Titanium, Lead, Tin, Zinc, Zirconium, Precious, Reactive, Refractory Metals and Alloys: Materials for Thermostats, Electrical Heating and Resistance Contact, and Connectors