Study on Quenching and Tempering Process of 42CrMoVNb Steel for Class 14.9 High Strength Automotive Fasteners
The different quenching and tempering process results of 42CrMoVNb steel for class 14.9 high strength automotive fasteners were analyzed through chemical composition analysis,metallographic struc-ture observation,hardness and mechanical performance testing.The research showed that the hardness and strength had no significantly decrease when tempered between 580 ℃ and 600 ℃,which was due to the oc-currence of secondary hardening when tempering at about 580 ℃.When the tempering temperature excee-ded 600 ℃,the strength decreased rapidly.The grain size of 42CrMoVNb obtained by Q9 process with higher austenitizing temperature was coarser than that Q3 process with lower austenitizing temperature.The higher the austenitization temperature,the higher the strength and hardness.The best quenching and tempe-ring processes for 42CrMoVNb steel were 940 ℃ × 40 min,oil cooling+590 ℃ × 60 min,air cooling and 940 ℃ ×45 min,oil cooling+595 ℃ ×90 min,air cooling.
class 14.9automotive fastenersquenching and tempering process42CrMoVNb steel
万方数据
维普
