EFFECT OF CRYSTALLOGRAPHIC ORIENTATION ON CUTTING FORCES AND SURFACE FINISH IN DUCTILE CUTTING OF KDP CRYSTALS

• Published in: Machining science and technology Vol. 15; no. 2; pp. 231 - 242
• Main Authors: Chen, Haofeng, Dai, Yifan, Zheng, Ziwen, Gao, Hang, Li, Xiaoping
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Taylor & Francis Group 15.04.2011; Taylor & Francis
• Subjects: Applied sciences; crystallographic orientation; Crystallography; Cutting; cutting force; Cutting parameters; Cutting tool materials; Exact sciences and technology; KDP crystal; KDP crystals; maximum undeformed chip thickness; Mechanical engineering. Machine design; Orientation; Precision engineering, watch making; Surface finish; Surface roughness; Phosphates; Atomic force microscopy; Crystal orientation; Precision engineering; High precision; Roughness; Machining; Surface forces; KDP crystal; surface finish; Ductile material; Surface conditions; Cutting force; maximum undeformed chip thickness; Crystallographic direction; Diamond tool; Chip formation; crystallographic orientation; Anisotropic material; Rough surface; Experimental study; Spectral analysis; Operating conditions; Smooth surface; Power spectrum
• ISSN: 1091-0344; 1532-2483
• DOI: 10.1080/10910344.2011.580701

In order to investigate the influence of material anisotropy in ductile cutting of Potassium Dihydrogen Phosphate (KDP) crystals, experiments of face cutting of (001) plane of KDP crystals are carried out by using an ultra-precision lathe with a single point diamond tool. The cutting forces, surface finish, and surface roughness in all crystallographic orientations of the machined surface are measured, and a power spectrum analysis method is used to reveal the cutting force patterns. The experimental results show that the cutting forces and surface roughness vary greatly with different crystallographic orientations of KDP crystal, and that amplitude variation of cutting forces and surface finish is closely related with the cutting parameter of the maximum undeformed chip thickness. With the maximum undeformed chip thickness below 30 nm, the amplitude variation of cutting force and surface finish is minimized, and a super-smooth surface with consistent surface finish in all the crystallographic orientations can be achieved. The surface roughness is 2.698 nm (Ra) measured by Atomic Force Microscope (AFM). These findings provide criteria for achieving a large-scale KDP crystal with consistent super-smooth surface using ductile cutting technology.