1、SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirelyvoluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefro
2、m, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions.QUESTIONS REGARDING THIS DOCUMENT: (412) 772-8512 FAX: (412) 776-0243TO PLACE A DOCUMENT
3、 ORDER; (412) 776-4970 FAX: (412) 776-0790SAE WEB ADDRESS http:/www.sae.orgCopyright 1989 Society of Automotive Engineers, Inc.All rights reserved. Printed in U.S.A.SURFACEVEHICLE400 Commonwealth Drive, Warrendale, PA 15096-0001INFORMATIONREPORTJ469REAF.JAN89Issued 1934-06Reaffirmed 1989-01Supercedi
4、ng J469 JUN83ZINC DIE CASTING ALLOYSForewordThis Document has not changed other than to put it into the new SAE Technical Standards BoardFormat.1. ScopeBecause of the drastic chilling involved in die casting and the fact that the solid solubilities of bothaluminum and copper in zinc change with temp
5、erature, these alloys are subject to some aging changes, one ofwhich is a dimensional change. Both of the alloys undergo a slight shrinkage after casting, which at roomtemperature is about two-thirds complete in five weeks. It is possible to accelerate this shrinkage by astabilizing anneal, after wh
6、ich no further changes occur. The recommended stabilizing anneal is 3 to 6 h at100 C (212 F), or 5 to 10 h at 85 C (185 F), or 10 to 20 h at 70 C (158 F). The time in each case ismeasured from the time at which the castings reach the annealing temperature. The parts may be air cooledafter annealing.
7、 Such a treatment will cause a shrinkage (0.0004 in per in) of about two-thirds of the total, andthe remaining shrinkage will occur at room temperature during the subsequent few weeks. Stabilizing resultsin a decrease in dimensions of about 0.0005 in per in from the original size of the casting. Sta
8、bilizing is, ofcourse, unnecessary if the machine or fitting operations can be delayed until the castings have aged fiveweeks at room temperature.When exposed to stagnant moisture or condensation with limited access to oxygen, a nonuniform type ofcorrosion may occur on zinc die castings, which often
9、 results in the formation of a bulky film of white corrosionproducts. This may hinder the operation of such parts as automobile lock cylinders, fuel pumps, andcarburetors, and in severe cases result in rather rapid loss of zinc. Various types of chromate films areavailable to satisfactorily overcome
10、 this condition.The same electroplating or enameling procedure is used with both alloys. Organic finishes are quite variablein their ability to adhere well to zinc surfaces. The phosphate type of chemical pretreatment has receivedwidest commercial utilization, and most zinc die castings which are to
11、 be finished with lacquers or enamels arephosphate pretreated. In general, a much wider selection of finishes can be used on pretreated die castings.The relative merits of the two SAE alloys may be outlined as follows:COPYRIGHT Society of Automotive Engineers, Inc.Licensed by Information Handling Se
12、rvicesSAE J469 Reaffirmed JAN89-2-2. ReferencesThere are no referenced publications specified herein.3. Z33520When the shrinkage referred to above has been removed by normal aging or by a stabilizing anneal,the dynamic and dimensional properties of this alloy are permanent at service temperatures up
13、 to 100 C(212F). Castings stabilized at elevated or at room temperature prior to final machining, assembling, or otheradjusting of dimensions will permanently maintain such dimensions within a tolerance of 0.00025 in per in inthe absence of excessive moisture. When exposed to high humidity and tempe
14、rature (as wet steam atatmospheric pressure or humid tropical climates), any change of either properties or dimensions will be onlythat resulting from surface corrosion analogous to that occurring in any other materials which are not totallyresistant to oxidation.4. Z35531This alloy is somewhat stro
15、nger and harder than Z33520. At room temperature, it is equal to Z33520in permanence of dimensions and impact strength. At elevated temperatures it is subject to slight growth indimensions and some loss of impact strength.COPYRIGHT Society of Automotive Engineers, Inc.Licensed by Information Handlin
16、g ServicesSAE J469 Reaffirmed JAN89-3-PREPARED BY THE SAE WROUGHT ALUMINUM COMMITTEE TABLE 1TYPICAL PHYSICAL AND MECHANICAL PROPERTIES IN THE AS-CAST STATE AT ROOM TEMPERATUREPhysical PropertiesAlloy AlloySI Units Z33520 Z35531(1)1. Die castings of alloy Z35531 shall not be used in applications wher
17、e they will be subjected to prolonged temperature, above 93.3 C (200 F).English Units Z33520 Z35531(1)Density, g/cm3 at 21C 6.6 6.7 Density, lb/cu in at 70 F 0.24 0.24Solidification Shrinkage, % 1.17 1.17 Solidification Shrinkage, % 1.17 1.17Solidification Temperature Range, C 387-381 386-380 Solidi
18、fication Temperature Range, F 728-718 727-717Thermal Expansion, mm/mm/C at 20-100 C (x 10-6)27.4 27.4 Thermal Expansion, in/in/F at 68-212 F 15.2 15.2Specific Heat Capacity, J/kg/C at 20-100 C418.7 418.7 Specific Heat Capacity, BTU/lb/F at 68-212 F 0.10 0.10Thermal Conductivity, W/m/C at 70-140 C113
19、.0 108.9 Thermal Conductivity, BTU/ft/h/ft2/F 65.3 62.9Electrical Conductivity, % IACS 27 26 Electrical Conductivity, % IACS 27 26Electrical Resistivity, ohm-cm at 20C6.3694 6.5359 _Mechanical PropertiesAlloy AlloySI Units Z33520 Z35531(1) English Units Z33520 Z35531(1)Ultimate Tensile Strength(2),M
20、Pa2. Tensile properties are determined from test specimens cast in a die and conforming to chemical composition specified. Test bars machined from castings do not provide a reliable measure of the strength properties of the casting and this method should not be used to determine conformance to data
21、shown in Table 1.283 328 Ultimate Tensile Strength(2), ksi 41 47.6Elongation (in 51 mm), % 10 7 Elongation (in 2 in), % 10 7Hardness, Brinell 500 kg 82 91 Hardness, Brinell 500 kg 82 91Shear Strength, MPa 214 262.0 Shear Strength, ksi 31 38Compressive Strength, Mpa - 0.1% Offset - Failure or Fractur
22、e414 600 Compressive Strength, ksi - 0.1% Offset - Failure or Fracture60 87Impact Strength(3), Joules (6.35 mm x 6.35 mm bar) unnotched)3. Impact strength drops rapidly below 0C (32F) to approximately 2.95 J (4 ft-lb) at 20 C (4 F) and 1.48 J (2 ft-lb) at 40 C (40F).58 65 Impact Strength(3), ft-lb (
23、1/4 in x 1/4 in bar unnotched)43 48Fatigue Strength, Mpa (5 x 108 cycles) 48 57 Fatigue Strength, ksi (5 x 108 cycles) 6.9 8.2Note: Unit is ksi (4 places)COPYRIGHT Society of Automotive Engineers, Inc.Licensed by Information Handling ServicesSAE J469 Reaffirmed JAN89RationaleNot applicable.Relationship of SAE Standard to ISO StandardNot applicable.ApplicationNot applicable.Reference SectionThere are no referenced publications specified herein.Developed by the SAE Wrought Aluminum CommitteeCOPYRIGHT Society of Automotive Engineers, Inc.Licensed by Information Handling Services
