1、 WORLDWIDE ENGINEERING STANDARDS Material Specification GMW3341 Pressure Die Casting Zinc Alloys Copyright 2011 General Motors Company All Rights Reserved December 2011 Originating Department: North American Engineering Standards Page 1 of 10 1 Scope This material specification applies to zinc alloy
2、s for use in high pressure die cast automotive applications and other allied industries. Zinc die casting alloys are specified by chemical composition. The alloys indicated represent common materials for identical product requirements across GM worldwide. 1.1 Material Description. Zinc base casting
3、alloys use aluminum and copper as the primary alloying elements with small amounts of magnesium added to minimize susceptibility to intergranular corrosion. The alloying elements determine the primary phases that give the material its mechanical and physical properties. The primary phases that are f
4、ormed (see 3.3) results in three distinct alloy groups which are described in Table A1 in Appendix A. High pressure zinc die castings are also characterized by excellent castability and wear properties. Zinc alloy castings are to be made from ingots that meet the requirements of the global specifica
5、tion for Zinc Alloy Ingots for High Pressure Die Casting, GMW3344. 1.2 Symbols. Not applicable. 1.3 Typical Applications. Because of their higher density, zinc alloy castings are less widely used in automotive applications than they were historically. They still do have a place, however, where intri
6、cate castability and high strength coincide. Typical applications and alloy selection criteria for major subsystems are provided in Table B1 in Appendix B. Zinc alloys are capable of being die cast with complex details, close tolerances and thin walls, thus making them attractive for many automotive
7、 applications. Both Zamak and ZA alloys are used for decorative and non-structural applications and, in some cases, the ZA alloys are also used for structural components. ACuZinc is a patented family of zinc casting alloys developed by General Motors. The ACuZinc alloys have higher strength and hard
8、ness and better creep and wear properties than the Zamak and ZA alloys. This makes them suitable for a variety of applications where the Zamak and ZA alloys are unsuitable. 1.4 Remarks. Table A1 in Appendix A contains a cross reference between GMW3341 alloy grades and their respective commercial all
9、oy designations, American and European standards and is presented for reference only. GMW3341 requirements may differ from those in other specifications. Cross referenced alloys are not interchangeable with their GMW3341 counterpart. 2 References Note: Only the latest approved standards are applicab
10、le unless otherwise specified. 2.1 External Standards/Specifications. ASTM B86 EN 12844 ISO 9915 SAE J468 ASTM B894 ISO 6506 ISO 9916 ASTM E536 ISO 6892 KS D 6005 2.2 GM Standards/Specifications. GMW3059 GMW3344 2.3 Additional References. TMC003 Material Safety Data Sheet guidance documents (availab
11、le at ). Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3341 Copyright 2011 General Motors Company All Rights Reserved December 2011 Pag
12、e 2 of 10 3 Requirements 3.1 Chemical Requirements. Castings furnished to this specification shall conform to the chemical composition limits shown in Table 1. Exceptions to GMW3341 composition requirements require agreement from purchaser (Design Responsible Engineer or delegate), and shall be expl
13、icitly documented on the GM engineering drawing and other equivalent part specification documents. Table 1: Chemical Composition for GMW3341 Zinc Alloys Element Note 1 Al Cu Mg Fe Pb Cd Sn Al4Mg 3.5 to 4.3 0.25 max. 0.02 to 0.06 0.10 max. 0.005 max. 0.004 max. 0.003 max. Al4Cu1Mg 3.5 to 4.3 0.75 to
14、1.25 0.02 to 0.08 0.10 max. 0.005 max. 0.004 max. 0.003 max. Al4Cu3Mg 3.5 to 4.3 2.5 to 3.3 0.02 to 0.05 0.10 max. 0.005 max. 0.004 max. 0.003 max. Al18Cu1Mg 8.0 to 8.8 0.8 to 1.3 0.015 to 0.03 0.075 max. 0.006 max. 0.006 max. 0.003 max. Al11Cu1Mg 10.5 to 11.5 0.15 to 1.2 0.15 to 0.02 0.075 max. 0.0
15、06 max. 0.006 max. 0.003 max. Al27Cu2Mg 25.0 to 28.0 2.0 to 2.5 0.01 to 0.02 0.075 max. 0.006 max. 0.006 max. 0.003 max. Cu6Al3Mg 2.8 to 3.3 5.0 to 6.0 0.025 to 0.05 0.075 max. 0.005 max. 0.004 max. 0.003 max. Cu10Al4Mg 3.0 to 4.0 10.0 to 11.0 0.025 to 0.05 0.075 max. 0.005 max. 0.004 max. 0.003 max
16、. Note 1: Composition limits in % by weight. Remainder of each alloy is Zn. 3.1.1 Chemical Analysis. The casting producer shall control chemical composition with samples taken from the melt prior to casting and solidified in a metallic die. Chemistry shall be measured in accordance with procedures,
17、master samples and calibration per ASTM E536, or equivalent. 3.2 Casting Requirements. Castings furnished shall be free from cold laps, misruns, hot tears, cracks, macroporosity, shrinkage, dross, mold material and lubricants, entrapped air and any other discontinuities, all to an extent that would
18、be detrimental to machinability, appearance, or performance. These discontinuities, plus surface roughness, casting cleanliness and weight of retained material, may have maximum allowable limits specified. For any of the above casting requirements, a measurement system shall be agreed upon by suppli
19、er and purchaser (Design Responsible Engineer or delegate). 3.3 Microstructure Requirements. The microstructures of castings are influenced by alloy composition, casting process parameters and thermal history. The Zamak alloys are characterized by the primary phase (zinc solid solution) while the ZA
20、 alloys are characterized by primary phase the (aluminum solid solution). ACuZinc alloys are characterized by primary phase (copper rich phase; Zn4 Cu). Any special requirements with regards to microstructure shall be agreed upon between the purchaser and supplier and specified on the engineering dr
21、awing. 3.4 Mechanical Properties. This specification does not govern mechanical properties. Mechanical properties are significantly influenced by alloy composition and casting process parameters, such as molten metal handling practice, casting process and thermal history. Properties of test specimen
22、s excised from castings will differ from cast-to-shape test bars due to differences in solidification conditions and thermal history. Therefore, any specific property required from a particular casting or section of a casting shall be called out separately on the GM engineering drawing and other equ
23、ivalent part specification documents. Typical mechanical properties associated with each alloy grade are shown in Appendix C. 3.4.1 Specification of Mechanical Properties. By agreement between supplier and purchaser (Design Responsible Engineer or delegate) hardness and mechanical property requireme
24、nts may be specified on the GM engineering drawing and other equivalent part specification documents. Unless otherwise specified, testing shall be done in accordance with ISO 6506 for hardness and ISO 6892 for tensile properties. The supplier and purchaser (Design Responsible Engineer or delegate) s
25、hall agree on a sampling plan. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3341 Copyright 2011 General Motors Company All Rights Rese
26、rved December 2011 Page 3 of 10 3.5 Physical Properties. By agreement between supplier and purchaser (Design Responsible Engineer or delegate) electrical conductivity requirements may be specified on the GM engineering drawing and other equivalent part specification documents. Typical physical prope
27、rties associated with each alloy grade are shown in Appendix D. 4 Manufacturing Process The selection of the casting process shall be a joint agreement between the purchaser and the supplier. 4.1 Casting. Castings are made using the hot chamber, high pressure die casting and the cold chamber, high p
28、ressure die casting processes. The preferred die casting process for each grade is shown in Table 2. Table 2: Alloys Listed by Casting Process Hot Chamber Process Note 1 Cold Chamber Process Note 2 AI4Mg AI11Cu1Mg AI4Cu1Mg AI27Cu2Mg AI4Cu3Mg Cu10AI4Mg AI8Cu1Mg Cu6AI3Mg Note 1: Hot Chamber, High Pres
29、sure Die Casting Utilizes high pressure and injection to fill the mold cavity that is made of tool steel. In addition, the hot chamber utilizes a metal pump that is immersed in the molten bath, to pump metal through a gooseneck and nozzle into the die cavity. Note 2: Cold Chamber, High Pressure Die
30、Casting Utilizes a high pressure die cast machine that has the molten zinc poured by hand or by an automatic ladle into a separate non-immersed shot sleeve for each cycle. 4.2 Heat Treatment. The rapid chilling rate inherent in zinc die castings results in minor property and dimensional changes with
31、 time. Some zinc alloys undergo a slight shrinkage (0.5 to 1.0 m per mm) when allowed to age at room temperature for period up to 6 months. For rigid dimensional requirements a stabilization anneal may be specified by adding an SA suffix to the alloy callout per Section 8. If specified, a stabilizat
32、ion anneal commonly recommended is a heat treatment consisting of 3 to 6 hours at 100 C. Heat treatment time is measured from the time at which the castings reach the annealing temperature. 4.3 Post Processing. Post processing of castings is normally limited to a trimming operation. However, a varie
33、ty of finishes are applicable for improved corrosion protection or appearance. Painting and electroplating are common. Chromating and phosphating are effective pre-treatments for paints and lacquers. Anodizing provides excellent corrosion resistance. Castings shall not be welded except with the perm
34、ission of the purchaser. 4.4 Inspection. Visual inspection, dimensional or non-destructive evaluation such as radiography or radioscopy to ISO 9915, liquid penetrant inspection per ISO 9916 and pressure tightness may be specified. 5 Rules and Regulations 5.1 Legal Regulations. All materials must sat
35、isfy applicable laws, rules, regulations and recommendations valid in the country of usage. 5.2 Language. In the event of conflict between the English and domestic language, the English language shall take precedence. 5.3 Inspection and Rejection. Samples of components or materials released to a GM
36、material specification shall be tested for conformity with the requirements of this material specification and approved by the responsible Engineering department prior to commencement of delivery of bulk supplies. A new approval must be received for any changes, e.g., properties, manufacturing proce
37、ss, location of manufacture, etc. If not otherwise agreed, all testing and documentation normally required for initial release must be completed. It is the responsibility of the supplier to inform the customer in a timely manner, without solicitation, and to include documentation of all modification
38、s of materials and/or processes and to apply for a new release. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3341 Copyright 2011 Gener
39、al Motors Company All Rights Reserved December 2011 Page 4 of 10 If not otherwise agreed, all release tests shall be repeated and documented by the supplier prior to commencement of delivery of non-conforming bulk supplies. In individual cases, a shorter test can be agreed to between the responsible
40、 Engineering department and the supplier. 5.4 Initial Source Approval. No shipments shall be made by any supplier until representative initial production samples have been approved by the appropriate Materials Engineering department(s) as meeting the requirements of this specification. 5.5 Material
41、Safety Data Sheets/Safety Data Sheets (MSDS/SDS). For new product submissions, or when a change in chemical composition of an existing product has occurred, a complete copy of the Material Safety Data Sheet/Safety Data Sheet must be submitted in compliance with the Globally Harmonized System of Clas
42、sification and Labeling of Chemicals (GHS) requirements or other country-specific MSDS/SDS requirements. In addition, product MSDS/SDS submissions must be in compliance with specific country General Motors TMC003 Material Safety Data Sheet/Safety Data Sheet guidance documents where available. 5.6 Al
43、l materials supplied to this standard must comply with the requirements of GMW3059, Restricted and Reportable Substances for Parts. 6 Approved Sources Engineering qualifications of an approved source are required for this standard. Only sources listed in the GM Materials File (i.e., GM Supply Power)
44、 under this standard number have been qualified by Engineering as meeting the requirements of this standard. For other GM locations, the responsible Engineering group should be contacted to obtain the approved source in that individual country. 7 Notes 7.1 Glossary. Not applicable. 7.2 Acronyms, Abb
45、reviations, and Symbols. GHS Globally Harmonized System MSDS Material Safety Data Sheets PPAP Production Part Approval Process SA Stabilization Anneal SDS Safety Data Sheets 8 Coding System This standard and any exceptions shall be referenced in the GM engineering drawing and other equivalent part s
46、pecification documents as illustrated by the example in Figure 1. The International Standard code of designation for cast zinc alloys is base on chemical symbols and usage illustrated in Appendix E. GMW3341M-ZN-C-D-Al4Cu1Mg-SA Temper code (Stabilization Anneal) Alloy code (Table 1) Process code (Die
47、 Cast) Forming code (Casting) Category (Zinc) Material type (Metal) Continuous number GM Worldwide Figure 1: Alloy Callout Example with All Required Codes Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted w
48、ithout license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3341 Copyright 2011 General Motors Company All Rights Reserved December 2011 Page 5 of 10 9 Release and Revisions This standard was originated in April 2000. It was first approved in October 2000. It was first published in October 200
49、0. Issue Publication Date Description (Organization) 1 OCT 2000 Initial publication. 2 DEC 2011 Refreshed. (Nonferrous Metals/Castings GSSLT) Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3341 Copyright 2011 General Motors Company All Ri
