ABSTRACT

Inconel 625 is a nickel-based super alloy especially used in aeronautical industries, due to its high mechanical strength, exceptional weldability and good corrosion resistance properties. However, machinability of Inconel 625 is quite challenging because of high-level heat generation in the cutting zone. In this work, to improve sustainable machining of Inconel 625; cryogenic CO₂ and LN₂ have been used as lubricants. Face milling was performed at two feed rates (f) of 0.2 and 0.6 mm/rev and spindle speeds (n) of 509 and 764 rpm with cryogenic (CO₂ and LN₂) cooling environments. The resulting surface characteristics, such as morphology, topography, micro-hardness and residual stress, along with chip morphology and tool wear, were investigated. Both cryogenic lubricants offered relatively better results at lower feed rate (f) and spindle speed (n). While cryogenic CO₂ provided better surface morphology and topography, LN₂ provided lower residual stress and higher surface micro-hardness.

摘要

Inconel 625 是一种镍基超级合金，由于其高机械强度、出色的可焊性和良好的耐腐蚀性能，特别用于航空工业。然而，Inconel 625 的可加工性非常具有挑战性，因为切削区会产生大量热量。在这项工作中，改进 Inconel 625 的可持续加工；低温CO ₂和LN ₂已被用作润滑剂。面铣削以 0.2 和 0.6 mm/rev 的两种进给率 ( f ) 和509 和 764 rpm 的主轴转速 ( n ) 进行，使用低温（CO ₂和 LN ₂) 冷却环境。研究了由此产生的表面特征，如形态、形貌、显微硬度和残余应力，以及切屑形态和刀具磨损。两种低温润滑剂在较低的进给率 ( f ) 和主轴速度 ( n )下都能提供相对更好的结果。虽然低温 CO ₂提供了更好的表面形态和形貌，但 LN ₂提供了更低的残余应力和更高的表面显微硬度。