QCT273-99标准（英文版）

Explanation about Standard Number PortabilityAccording to the requirement No. 1998216 of standard letter issued by State Administration of Quality Technical Supervision and written reply No.1999126 of State Bureau of Machine Building Industry, the original standard number ZB T05 002-89 is transformed to trade standard number QC/T 273-1999, but the contents wont be changed temporarily. Please use new standard numbers when quoting. PRC Trade StandardZB T05 002-89Technical Condition of Zinc Alloy, Aluminum Alloy and Copper Alloy Die-Casting Parts for Automobile 1 Contents and application scopeThis standard stipulates technical requirement, inspection method, inspection rules, identification and packaging of zinc alloy, aluminum alloy and copper alloy die-casting parts for automobile.This standard is applicable to zinc alloy, aluminum alloy and copper alloy die-casting parts on automobile.2 Normative referenceGB228Test method of metal pullGB231Test method of metal Shore hardnessJB3072Test specimens for non ferrous die-casting alloysZBT04 006.4Limit offset for castings of unnoted tolerance 3 Technical requirement3.1 Chemical composition of zinc alloy, aluminum alloy and copper alloy is as shown in table 1, table 2 and table 3. Table 1 %Alloy designationAlloy codeMain compositionImpurity (no more than)AlCuMg Zn Fe Pb Sn Cd Total YZZnAl4CU1Y413.54.50.751.250.030.08Other 0.10.0050.0030.0050.2YZZnAl4Y403.54.50.10.030.08Other 0.10.0050.0030.0050.2 Table 2 %Alloy designationAlloy codeMain compositionImpurity (no more than)SiCuMgMn Al Fe Sn Zn Mn Cu TotalYZAlSi12Y10210.013.0-Other 1.2-0.30.60.62.3YZAlSi10MgY1048.010.5-0.170.30.20.5Other 1.0-0.3-0.31.5YZAlSi12Cu2Y10811.013.01.02.00.41.00.80.9Other 1.00.011.0-2.0YZAlSi9Cu4Y1127.59.53.04.00.10.30.20.5Other 1.00.11.2-2.0 Approved by PRC Automobile Industry Union on Dec. 7, 1989 Implemented on April 1, 1990 ZB T05 002-89 Table 3 %Alloy designationAlloy codeMain compositionImpurity (no more than)Cu Pb Zn Fe Al Sb Total YZCuZn40Pb1Y59157610.81.9Other 0.80.20.051.503.2 Mechanical performance of alloy is as shown in table 4.Table 4Alloy categoryAlloy designationMechanical performance (no less than)Tensile strength b (Mpa)Extension rate (%)Hardness HBZn alloyYZZnAl4Cu1275290YZZnAl4255180Aluminum alloyYZAlSi12220260YZAlSi10Mg220270YZAlSi12Cu2240190YZAlSi9Cu4240185Cu alloyYZCuZn40Pb131581003.3 Dimension of castings should meet the requirement pf product drawing.3.4 Limit offset of unnoted tolerance should meet the provision of ZB T04 006.4.3.5 Surface quality3.5.1 Surface roughness of castings: for zinc alloy an aluminum alloy, it is no more than R 3.2; for copper alloy, it is no more than R 6.3. For roughness of decorative surfaces which need to be polished and anode oxydation treated, aluminum alloy and zinc alloy are no more than Ra 1.6, and copper alloy is no more than Ra 3.2.3.5.2 Castings should not have such as omitted casting, crack, cold lap at corresponding position of the same part, defects difficult to be removed by machining.3.5.3 Pouring, overflowing hole, flash ect. of castings should be removed and marks of no bigger than 0.3 mm is allowed.3.5.4 Height of netlike burs and marks on unmachined faces of castings: for zinc alloy and aluminum alloy, it is no more than 0.1 mm; for copper alloy, it is no more than 0.2 mm. Concave and convex depth of push rod mark is no more than 0.4 mm and mark is no more than 0.3 mm after burs and scrap in holes are removed.3.5.5 There should be no any protruding mark on process reference face and fitting face, no mark of push rod on decorative face. These surfaces should be noted in casting drawing.3.5.6 Defects which can be removed by polishing such as Pattern, stream, scrape and mark are permissible on decorative surfaces.3.5.7 There should be no local cast peel affecting usage on machined surfaces of castings. Dispersive tiny air holes which dont affect connecting tightness are allowed to appear on joint faces.3.5.8 The first two teeth of castings thread after machined should not have casting defects which affect screwing operation, and the rest threads should not have any air hole of diameter more than 1 mm.3.6 Defects of castings can be reasonably technically repaired by finishing, rectifying and supplementary mechanic way, but the requirement of the drawing and this standard must be complied with.3.7 Casting pitch3.7.1 Casting pitch will not be reckoned in tolerance range.3.7.2 The general casting pitch of all kinds of alloy castings cavity must meet the provision of table 5 and that of outer wall of castings is its 1/2. Table 5Cavity depth of castings (mm)Material of castings6688101015152020303060Zinc alloy23021451301151045Aluminum alloy433032302130115Copper alloy54330323021303.7.3 Relationship between hole diameter and max. hole depth of castings and casting pitch must meet the provision of table 6. Table 6Hole diameter D (mm)Zinc alloyAluminum alloyCopper alloyMax. depth (mm)Casting pitchMax. depth (mm)Casting pitchMax. depth (mm)Casting pitch-89130823034141201824518110161455620118140683205025130142308104004538115252101250040501103014512168003080145115162011002511004570120251500201500404 Inspection method4.1 The determination of tensile strength and extension rate shall be done as per the provision of GB 228.4.2 The determination of hardness shall be done as per the provision of GB 231.4.3 Shape and dimension of test sample should be in accordance with JB 3072.4.4 The determination of chemical composition of castings shall be done according to relevant standard of metallurgy department and it may also be done by other way if accuracy can be guaranteed. 5 Inspection rules5.1 Castings must be inspected and accepted by technical inspection department of manufacturer according to casting drawing and the provision of technical documentations. The demander may carry out reinspection on quality of castings.5.2 Inspection requirement of chemical composition and mechanic performance of castings is divided into four categories seen in table 7. The category of castings shall be discussed by relevant units and indicated in technical documentations. Those unnoted ones will go to category 4. Table 7Castings Category Inspection requirement1Chemical composition, mechanical performance2Chemical composition3Mechanical performance4No inspection5.3 For castings whose chemical composition needs to be inspected, take one group of samples from each oven. However, for cast-hardened products with stable raw material and process, sample or carry out spot inspection by shift. For those with special requirement of inspection frequency, discuss about it separately.5.4 If chemical composition of castings is not conforming for the first determination, sample newly. Castings of this oven will be regarded as unqualified products in case of further failure.5.5 For castings whose mechanical performance needs to be inspected, carry out spot inspection regularly. For cast-hardened products with stable raw material and process, inspection cycle can be extended. For those with special requirement of inspection frequency, discuss about it separately.5.6 The mechanical performance of castings refers to the performance of test bar and test sample for hardness test shall be taken from the top part of the sample for tensile test.Each gro