Custom 4140 Alloy Steel Parts

We offer comprehensive heat treatment including quenching and tempering (Q&T) to achieve 28-32 HRC, through-hardening to 58 HRC, case-hardening, induction hardening, and stress relieving. Heat treatment selection depends on your application requirements for hardness, toughness, and wear resistance.

4140 offers good strength and toughness at lower cost, while 4340 provides higher strength and impact resistance due to increased nickel content. 4140 is ideal for most applications, while 4340 is chosen for extreme loading conditions. Both respond well to heat treatment and machining.

Yes, we can machine hardened 4140 steel using hard turning and grinding operations. For best results, we typically machine parts in annealed condition, then heat treat to final hardness, followed by finish grinding if required. This approach ensures optimal surface finish and dimensional accuracy.

Our precision CNC machining capabilities allow tolerances as tight as ±0.01mm for critical dimensions. After heat treatment, finish grinding can maintain ±0.005mm tolerances. We use CMM inspection to verify dimensions and provide detailed inspection reports.

Yes, we provide complete material traceability including mill certificates with chemical composition analysis, mechanical property test reports, heat treatment records showing quench and temper parameters, hardness test results, and dimensional inspection reports meeting ASTM A322 and international standards.

Common surface treatments include black oxide for corrosion protection, zinc or nickel plating for enhanced corrosion resistance, phosphate coating before painting, and nitriding for increased surface hardness and wear resistance. Selection depends on your environmental conditions and performance requirements.