放电等离子烧结K403镍基高温合金渗铝层的制备及性能

Fabrication and performance of aluminized coating on K403 Ni-based superalloy sintered by spark plasma sintering

根据电场对原子扩散的促进作用,结合放电等离子烧结快速升降温的优点,实现镍基高温合金的快速渗铝,并研究渗铝温度对K403镍基高温合金渗铝组织结构的影响,以及渗铝后材料的高温抗氧化性能和摩擦磨损性能。结果表明,900℃渗铝30 min,获得了厚度约为109μm的渗铝层,属于低温高活度渗铝;1 000℃的渗铝层厚度约为89μm,属于高温低活度渗铝。经1 000℃氧化后,质量增加速率从未经处理镍基高温合金的2.5 mg/cm^2下降到渗铝镍基高温合金的1.3 mg/cm^2,降低48%。同时摩擦因数从1.2减小至0.6,降低50%。体积磨损率从4.08%下降至0.392%,降低90.4%。

According to the effect of electric field on atomic diffusion,combined with the advantages of pulse plasma sintering which rapid temperature rise and high cooling rate can be achieved to realize rapidly aluminizing of nickel base alloy.In this paper,the effect of aluminizing temperature on aluminized process of K403 nickel-based superalloy and the high temperature oxidation resistance and wear properties of the Ni-based superalloy were studied.The results show that the aluminized coating with a thickness of about 109μm is obtained through aluminized at 900℃for 30 min,which belongs to low temperature and high activity aluminizing.The thickness of aluminized layer at 1 000℃is about 89μm,which belongs to aluminizing at high temperature and low activity.After 1 000℃oxidation,the mass gain from 2.5 mg/cm^2 of untreated nickel-based superalloy decreases to 1.3 mg/cm^2 of the aluminized nickel-base superalloy,reduced by 48%.Meanwhile,the friction coefficient decreases by 50%from 1.2 to 0.6.The volume wear rate decreases from 4.08%to 0.392%,reduced by 90.4%.