限动芯棒的失效演变及质量改进

Failure Evolution and Quality Improvement of Mandrel

芯棒在使用过程中出现的失效形式为镀铬层的剥落、划伤、掉肉以及环裂等。通过现场跟踪掌握芯棒的失效演变过程,提出通过改进镀铬层的厚度及结合强度、调整芯棒回火工艺和硬度控制、提高调质后弯曲度以及改进镀前、镀后处理工艺等措施提高芯棒的质量。

The mandrel appears failure of chroming layer spalling,scratch,matrix spalling and annular crack during the use process.Through on-site tracking,the failure evolution have been obtained.The superior quality of the mandrel can be obtained by improving the chrome layer thickness and bonding strength,adjusting the mandrel tempering process and hardness control,raising the straightness of mandrel after quenching and tempering and optimizing before and after chroming process parameters and so on.