The failure mechanism of middle hole cores of H13 steel was analysed in thes paper.The influence of ion nitriding,gas nitrocarburizing and plasma spraying on their life was also researched.

• 分析了H13钢分流锥的失效机理，研究了离子渗氮、气体氮碳共渗及常压等离子喷涂等对其使用寿命的影响。