加压内冷却方法在高温合金磨削中的应用

Applications of Pressurized Internal Cooling Method in Superalloy Grinding Processes

针对镍基高温合金在磨削加工中大量磨削热的冷却问题,提出采用加压内冷却与断续磨削结合的冷却方法,实现磨削过程中充分冷却磨削弧区高温的目的。设计制备磨粒有序排布的加压内冷却砂轮,采用Fluent有限元软件建立砂轮磨削GH4169高温合金的温度场模型,模拟分析砂轮转速和冷却液压力对砂轮散热性能的影响。开展加压内冷却砂轮磨削GH4169实验研究,分别对磨削温度、表面粗糙度以及表面微观形貌进行对比和分析。结果表明:在相同的磨削参数条件下,相对外冷却方式,内冷却方式能获得更优良的加工表面质量,磨削温度和表面粗糙度均明显降低;在其他磨削参数相同时,冷却液压力越大,磨削温度越低且表面粗糙度越小,表面形貌更加规则、完整。

In view of the cooling problems of much grinding heats generated in the grinding processes of nickel-based superalloy,a cooling method that combined pressurized internal cooling and intermittent grinding was proposed to actively control the high temperatures of grinding arc areas effectively.The pressurized internal cooling wheel with abrasive orderly was designed and fabricated.The temperature field model of GH4169 superalloy grinding processes was established in Fluent software.The effects of wheel speeds and coolant pressures on the cooling performance of the grinding wheels were simulated and analyzed.The grinding experiments of GH4169 using press-internal cooling wheel was conducted,the grinding temperature,machined surface roughness and surface topography were compared and studied.The results show that：under the same grinding parameters,compared with external cooling,internal cooling method may obtain more excellent machining surface quality,the grinding temperatures and surface roughnesses are significantly lower;when other grinding parameters are the same,the greater coolant pressure,the lower grinding temperatures and surface roughnesses,meanwhile with better and more regular surface morphology.