1、 WORLDWIDE ENGINEERING STANDARDS Material Specification GMW16893 Medium Carbon, Alloyed Steel Barstock Copyright 2013 General Motors Company All Rights Reserved January 2013 Page 1 of 3 1 Scope This specification defines the metallurgical requirements for a continuously cast, aluminum killed, vacuum
2、 degassed, fine grained steel barstock to be used for camshafts with roller lifters. Bars purchased to this specification will be hot rolled, normalized, straightened, stress relieved, turned and polished. Material conforming to this specification will be induction hardenable, machinable and have a
3、controlled level of internal inclusions to assure part durability. 1.1 Material Description. Medium carbon alloyed steel barstock. 1.1.1 Material Identification. GMW16893. 1.2 Symbols. Not applicable. 1.3 Typical Applications. Camshafts with roller lifters. 2 References Note: Only the latest approve
4、d standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. ASTM E45 ISO 6506 2.2 GM Standards/Specifications. GMW3059 2.3 Additional References. TMC003 Material Safety Data Sheet guidance documents (available at ). 3 Requirements 3.1 Requirements on Delivery. 3.1.1
5、 Chemical Requirements. Chemical Composition. Material supplied to this specification shall conform to the following chemical composition (percent (%) by mass, product analysis). Carbon 0.48 to 0.53 Manganese 0.80 to 0.90 Silicon 0.15 to 0.30 Chromium 0.70 to 0.80 Phosphorus 0.030 maximum Sulfur 0.0
6、30 to 0.050 Aluminum 0.020 to 0.050 3.1.2 Mechanical Requirements. Hardness: Normalized barstock shall exhibit hardness of HBW 250 maximum when tested per ISO 6506. 3.1.3 Physical Requirements. Indigenous Inclusions: Microscopic inclusions resulting from deoxidation and/or limited solubility in soli
7、d steel. 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 GMW16893 Copyright 2013 General Motors Company All Rights Reserved January 2013 Pag
8、e 2 of 3 Steel shall meet the following inclusion rating maximum limits in 100% of specimens examined per ASTM E45 Method A. Critical regions for evaluation include the finish-machined bearing journal surfaces, and finish-machined lobes at ramps and nose locations to a depth of 0.5 mm. Type A (Sulfi
9、des) Thin = 4 Heavy = 2.5 Type B (Alumina) Thin = 2 Heavy = 1 Type C (Silicate) Thin = 1.5 Heavy = 1 Type D (Globular) Thin = 1.5 Heavy = 1 3.1.3.1 Exogenous Inclusions. Macroscopic inclusions from entrapped slag and/or refractories stepdown testing per ASTM E45 shall be used to evaluate cleanliness
10、 of rolled steel bars supplied by the mill. Five (5) 1 in. long steps with diameters incremented equally between the base circle diameter (minimum) and nose circle diameter (maximum) of a particular camshaft shall be turned on each specimen. Magnetic particle inspection technique shall be used to in
11、spect steps for globular and linear indications. Each specimen may contain up to 15 indications (no more than three (3) per step). Any such indications with a major dimension 1 mm are unacceptable. This test shall be conducted once per quarter or other agreed upon frequency. 3.1.4 Additional Require
12、ments. Microstructure. Material must be normalized to produce a fine pearlitic structure containing no more than 10% coarse pearlite (resolvable at 400 X). 3.2 Processing Requirements. Straightness must be maintained throughout the processing sequence. Bars should be stress relieved at approximately
13、 565 C to eliminate residual stresses. Surface Condition. Processed barstock (camshaft blanks) must be seam and decarburization free. 3.2.1 Requirements on Other Stages During Life Cycle. Components manufactured to this standard shall not have any negative effect on recyclability of the parts/vehicl
14、e. 4 Manufacturing Process Continuously cast, aluminum killed, vacuum degassed, fine grain, hot rolled, normalized alloyed steel barstock. 5 Rules and Regulations 5.1 Legal Regulations. All materials must satisfy applicable laws, rules, regulations and recommendations valid in the country of usage.
15、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 material specification shall be tested for conformity with the requirements of this material
16、 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 process, location of manufacture, etc. If not otherwise agreed, all testing and documentation nor
17、mally 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 modifications of materials and/or processes and to apply for a new release. If not otherwise agreed, all
18、 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 Engineering department and the supplier. 5.4 Material Safety Data Sheets/Safety Data Sheets
19、(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 Classification and Labeling of Chemicals (
20、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. 5.5 All materials supplied to this standard
21、must comply with the requirements of GMW3059, Restricted and Reportable Substances for Parts. 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 STANDARD
22、S GMW16893 Copyright 2013 General Motors Company All Rights Reserved January 2013 Page 3 of 3 6 Approved Sources Materials supplied to this specification must be approved by General Motors. The appropriate GM Materials Engineering department(s) must confirm material as meeting the requirements of th
23、is specification. Any test data sheets of material submitted to General Motors for such confirmation (e.g., during Production Part Approval Process (PPAP) under this material specification must list all properties and must apply corresponding test methods of this material specification. 7 Notes 7.1
24、Glossary. MATSPC: Global repository of GM approved materials for corresponding GM Engineering Standards. 7.2 Acronyms, Abbreviations, and Symbols. ASTM ASTM International GHS Globally Harmonized System of Classification and Labeling of Chemicals HBW Hardness, Brinel, Tungsten MSDS Material Safety Da
25、ta Sheet PPAP Production Part Approval Process SDS Safety Data Sheet 8 Coding System This standard shall be referenced in other documents, drawings, etc., as follows: Material per GMW16893 9 Release and Revisions This standard was originated in November 2012. It was first approved by the Ferrous (In
26、clu. Sheet Metal) Team in January 2013. It was first published in January 2013. Issue Publication Date Description (Organization) 1 JAN 2013 Initial Publication. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
