Steel sourcing for MSMEs: how to ensure consistent quality for auto parts

Sourcing steel for auto parts is critical for micro, small, and medium enterprises (MSMEs). The mechanical properties, metallurgical composition, and production consistency of the steel directly influence the performance, safety, and durability of auto components. Ensuring consistent quality requires a technical approach involving material selection, supplier evaluation, and compliance with industry standards. 

Key material properties for auto parts 

Steel used in auto parts must meet specific mechanical and metallurgical criteria to withstand operational stresses: 

1. Tensile strength (MPa): the maximum stress steel can endure tension before failure. Key for components like suspension and chassis parts. 

2. Yield strength (MPa): the stress at which steel starts deforming plastically. Higher yield strength is essential for structural integrity. 

3. Ductility (percentage elongation): indicates the steel's ability to stretch under stress, crucial for forming complex geometries. 

4. Corrosion resistance: ensures longevity when exposed to moisture, salts, or chemicals. 

5. Weldability: allows secure and robust joining of parts, critical for assemblies. 

6. Fatigue resistance: ensures durability under cyclic loads, such as those experienced by springs and axles. 

Selecting the right steel grades 

The choice of steel grade impacts component performance and manufacturing efficiency. Common grades include: 

1. High-strength low-alloy (HSLA) steel: 

• Yield strength: 250–550 MPa. 

• Application: frames, reinforcements, and crash-absorbing structures. 

1. Advanced high-strength steel (AHSS): 

• Dual-phase (DP) and transformation-induced plasticity (TRIP) steels. 

• Yield strength: up to 1200 MPa. 

• Application: safety-critical parts like door beams and roof structures. 

1. Galvanised steel: 

Coated with zinc for enhanced corrosion resistance. 

Application: body panels and underbody components. 

1. Stainless steel: 

Grades: 304, 316 for high corrosion and temperature resistance. 

Application: exhaust systems and high-heat zones. 

Sourcing from reliable suppliers 

Consistency in steel quality begins with supplier selection. Key steps include: 

1. Material certification: 

Ensure suppliers provide mill test certificates (MTC) and adhere to standards like BIS IS 2062, SAE J403, or ASTM A36. 

1. Manufacturing process evaluation: 

Assess whether suppliers use controlled processes like continuous casting, Ladle refining, vacuum degassing, or thermomechanical treatment (TMT). 

1. Traceability: 

Confirm that all batches of steel can be traced back to their source, ensuring uniformity and compliance with specifications. 

1. Inspection protocols: 

Perform supplier audits to ensure adherence to quality systems like ISO 9001 or IATF 16949. 

Quality assurance testing 

Technical testing of steel batches is crucial to verify compliance with specifications before production: 

1. Tensile testing: 

Conducted per ASTM E8 or IS 1608 to measure tensile and yield strength, elongation, and reduction in area. 

1. Impact testing: 

Charpy V-notch testing as per ASTM E23 or IS 1757 to determine toughness under dynamic loads. 

1. Microstructural analysis: 

Examination of grain size, phase distribution, and inclusions using optical or scanning electron microscopy (SEM). 

1. Corrosion resistance testing: 

Salt spray tests (ASTM B117) or cyclic corrosion tests to simulate long-term exposure. 

Leveraging platforms like JSW One MSME 

Platforms like JSW One MSME streamline steel sourcing for MSMEs by connecting them with pre-vetted suppliers. These platforms ensure material compliance through robust testing and certification processes and provide services like inventory management, logistics, and financing to optimise procurement. 

Conclusion 

Maintaining consistent steel quality for auto parts production requires a technical focus on material properties, rigorous testing, and adherence to standards. By working with reliable suppliers, conducting comprehensive quality checks, and leveraging platforms like JSW One MSME, MSMEs can ensure superior component performance and compliance with industry benchmarks.