The results show that hardness gradient becomes smooth and its peak value shifts inwards as high speed steel tools are treated by active screen plasma nitriding, their fatigue-resistant increases.

• 结果表明,经活性屏离子渗氮处理后,渗氮层硬度梯度变得平缓,且最高硬度不在表面,而是在距表面一定距离处,这将能提高高速钢的耐疲劳性能,改善高速钢的内在质量。