This specification covers the standard requirements for commercial zinc casting alloys in ingot form for use in the manufacture of sheet metal forming dies, sand cast or plaster cast forming dies, and plastic injection molds. Kirksite A alloy (UNS Z35543) is intended for use in the fabrication of dies for sheet metal stamping under drop hammer and hydraulic pressure while Kirksite B alloy (UNS Z35542) is a special purpose alloy of closely controlled composition and is primarily used in the manufacture of plastic injection molds. The alloys may be made by any approved process and shall be of uniform quality and free from dross, slag, or other harmful contamination. Jumbo or block ingots shall conform to the configuration, or to a shape and size previously agreed upon. Conformance with the composition requirements for aluminum, cadmium, copper, iron, lead, magnesium, tin and zinc shall be determined by spectrographic or chemical analysis. The samples for chemical analysis shall be taken from the material by drilling, sawing, milling, turning, or clipping a representative piece or pieces of the ingot.

1.1 This specification covers commercial zinc alloys in ingot form for remelting for the manufacture of dies and molds from the alloys as shown in Table 1.

1.2 This specification presents requirements for zinc alloys suitable for the production of sand cast or plaster cast forming dies for sheet metal stamping operations and plastic injection molding. Alloy A is intended for use in the fabrication of dies for sheet metal stamping under drop hammer and hydraulic pressure. Alloy B is a special purpose alloy of closely controlled composition and is primarily used in the manufacture of plastic injection molds.

1.3 This specification covers two zinc alloys which are specified and designated as follows:

1.4 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.

1.5 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.

TABLE 1 Chemical and North American Color Code Requirements^A,B

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

^B UNS designations were established in accordance with Practice E527.

^C Refer to Practice B908. (Note: Colors indicated are for North American applications.)