工程机械缸套等离子表面淬火热处理工艺及性能的研究

Study on Heat Treatment Process and Properties of Engineering Machinery Cylinder by Plasma Surface Quenching

工程机械缸套在运行过程中,容易产生因45钢硬度低而导致表面产生磨损失效的现象,缩短了缸套的使用寿命。针对这一缺点,本试验采用等离子表面淬火热处理工艺对工程机械缸套的内壁进行局部硬化处理,实现自激冷却淬火,生成硬度极高的淬火硬化层,组织为高硬度的隐针马氏体。结果表明：随工作电流的增加,淬火层硬度也趋于上升;而伴随着扫描速度或波头数的增大,单道与交叉道的硬度均呈下降趋势。经等离子表面淬火热处理后的试样表面比未淬火的原始试样耐磨性提高了5~6倍。

During the operation of engineering machinery cylinder,45 steel shows the wear failure phenomenon for the lack of wear resistance induced by the low hardness,which leads to reduce the lifespan of cylinder.In order to solute this problem,the inner surface of the engineering machinery cylinder was scanned and local hardened by the plasma surface quenching process.The inner surface of cylinder was self cooled and quenched to obtain the high hardness of quenched and hardened layer,together with the cryptocrystalline martensite of high hardness.The experimental results show that with the increase of current,the quenching hardness shows a rising trend.While with the increase of scanning speed or wave number,the hardness of the single channel and cross channel decreases.The abrasion resistance of the sample surface treated by plasma surface quenching increases 5-6 times than that of the original sample.