AWS D8.2M:2017 pdf download.Specification for Automotive Weld Quality - Resistance Spot Welding of Aluminum
1.1 Scope.
This specification expresses the quality characteristics and metrics pertinent to individual resistance spot welds on automotive aluminum structures. The acceptance criteria are the same for all welds regardless of the service load and intended to be applied in conditions typically encountered during manufacturing. Welds at variance from the stated weld quality criteria in this document can still have mechanical properties that satisfy product and design requirements as per agreement between customer and supplier. Any attempted application of this document or the evaluation criteria used herein to other uses, for example post-crash weld quality assessment, may lead to an erroneous result.
1.2 Units of Measurement. This standard makes sole use of the International System of Units (SI).
1.3 Safety. Safety issues and concerns are addressed in this standard, although health issues and concerns are beyond the scope of this standard. Safety and health information is available from the following sources:
American Welding Society:
(1) ANSI Z49.1, Safety in Welding, Cutting, and Allied Processes
(2) AWS Safety and Health Fact Sheets
(3) Other safety and health information on the AWS website
Material or Equipment Manufacturers:
(1) Safety Data Sheets supplied by materials manufacturers
(2) Operating Manuals supplied by equipment manufacturers
Applicable Regulatory Agencies
Work performed in accordance with this standard may involve the use of materials that have been deemed hazardous,and may involve operations or equipment that may cause injury or death. This standard does not purport to address all safety and health risks that may be encountered. The user of this standard should establish an appropriate safety program to address such risks as well as to meet applicable regulatory requirements. ANSI Z49.1 should be considered when developing the safety program.
interfacial fracture. A fracture mode of a spot weld where all of the weld nugget separates through the plane of the weld at the faying surface. If less than approximately 20% of the mating sheet thickness is removed, the fracture is interfacial (See example in Figure 16). This mode may or may not include some button pull or partial thickness fracture.
nugget. The weld metal joining the work pieces, consisting of the fusion zone (solidified metal), but excluding the heat affected zone.
partial thickness fracture. A fracture mode of a spot weld where a part of the weld nugget shows removal of parent metal by the weld from the mating sheet. This mode may or may not include some button pull or interfacial fracture.The portion removed must be approximately 20% of the mating sheet thickness, otherwise the fracture is interfacial.A cavity is left in the mating sheet (see example in Figure 12).
weld size. The average of the maximum and minimum dimensions of the fused area in destructive inspection or the nug-get width in metallographic inspection.
4. Weld Process Control
Production-welded parts being joined by the resistance spot welding process have inherent variability of weld character-istics. Therefore, the weld quality requirements must be consistent with the manufacturing process capabilities. The welding process must be controlled to achieve the minimum weld quality level required by the product design. Information and guidance pertaining to supplier requirements for process and product control are contained in the latest edition of ISO/TS 16949, Quality Systems - Particular Requirements for the Application of ISO 9001:2008 for automotive produc-tion and relevant service part organizations, published by the International Standards Organization (ISO).AWS D8.2M pdf download.