اثر میکروساختار ماده بر فرسایش ابزار هنگام ماشینکاری آلیاژهای Ti

 Experimental investigation on the effect of the material microstructure on tool wear when machining hard titanium alloys: Ti–6Al–4V and Ti-555

بررسی اثر میکروساختار ماده بر فرسایش ابزار هنگام ماشینکاری آلیاژهای سخت تیتانیوم :  Ti-555; Ti – 6Al – 4V

ABSTRACT

An experimental investigation was conducted in this work to analyze the effect of the workpiece microstructure on tool wear behavior and stability of the cutting process during marching difficult to cut titanium alloys: Ti–6Al–4V and Ti-555. The analysis of tool–chip interface parameters such as friction, temperature rise, tool wear and workpiece microstructure evolution under different cutting conditions have been investigated. As the cutting speed increases, mean cutting forces and temperature show different progressions depending on the considered microstructure. Results show that wear modes of cutting tools used for machining the Ti-555 alloy exhibit contrast from those obtained for machining the Ti–6Al–4V alloy. Because of the fine-sized microstructure of the near-β titanium Ti-555, abrasion mode was often found to be the dominate wear mode for cemented cutting tools. However, adhesion and diffusion modes followed by coating delamination process were found as the main wear modes when machining the usual Ti–6Al–4V alloy by the same cutting tools. Moreover, a deformed layer was detected using SEM–EDS analysis from the sub-surface of the chip with β-grains orientation along the chip flow direction. The analysis of the microstructure confirms the intense deformation of the machined surface and shows a texture modification. 

 

ماشین کاری تیتانیوم و آلیاژهای آن

MACHINING TITANIUM AND ITS ALLOYS

ماشین کاری تیتانیوم و آلیاژهای آن 

ABSTRACT

Titanium and its alloys are attractive materials due to their unique high strength-weight ratio that is maintained at elevated temperatures and their exceptional corrosion resistance. The major application of titanium has been in the aerospace industry. However, the focus shift of market trends from military to commercial and aerospace to industry has also been reported. On the other hand, titanium and its alloys are notorious for their poor thermal properties and are classified as difficult-to-machine materials. These properties limit the use of these materials especially in the commercial markets where cost is much more of a factor than in aerospace. Machining is an important manufacturing process because it is almost always involved if precision is required and is the most cost effective process for small volume production. This paper reviews the machining of titanium and its alloys and proposes potential research issue .