Manufacturing Technology Today

Jatinder Kumar ¹, J. S. Khamba ²

Affiliations
1 Dept. of Industrial Engg., National Institute of Technology, Kurukshetra, Patiala, IN
2 Dept. of Mechanical Engg., Univ. College of Engg., Punjabi University, Patiala, IN

Abstract

This paper initially reviews the research on machining of titanium with conventional methods and ultrasonic machining process. Experimental research is subsequently presented on ultrasonic drilling of titanium (ASTM Grade-I) under established experimental conditions using two different tool materials-high carbon steel and titanium alloy; three different abrasive materials-alumina, silicon carbide and boron carbide with three different grit sizes-220, 320 and 500. The results obtained for machining rate and tool wear rate were presented as main effects plots. It was concluded that tool material properties such as hardness, fracture toughness affect the machining performance of USM very significantly. Machining efficiency is also found to improve with increase in the hardness and coarseness of the abrasive media used for preparation of the slurry.

Full Text

     

Jatinder Kumar ¹, J. S. Khamba ², S. K. Mohapatra ³

Affiliations
1 Dept. of Mechanical Engg., AKGEC, Ghaziabad, IN
2 Dept. of Mechanical Engg, UCOE, Punjabi University, Patiala, IN
3 Dept. of Mechanical Engg., TIET, Patiala, IN

Abstract

Ultrasonic Machining is one of the most widely used non-traditional machining processes for the machining of non-conductive, brittle materials such as engineering ceramics. Although USM can machine any material regardless of its electrical conductivity, the machining performance of this process is dependent on several important mechanical properties of the work material being machined, including fracture toughness and hardness. There is a considerable lack of research on this aspect of USM, particularly the performance of the process with different work-tool combinations and under varying process conditions such as slurry grit size, tool material, abrasive material etc. In the present investigation, an experimental study has been conducted to assess the effect of slurry grit size on Machining rate and tool wear rate with twelve different work-tool combinations. It has been concluded that the abrasive grit size plays an important role in the variation of the machining performance of USM. The machining rate is found to decrease with a corresponding increase in the product of fracture toughness and hardness of the work material. Tool wear rate decreases with decrease in the fracture toughness of work material and increase in the strain hardening capability of tool material.

Full Text

     

Jatinder Kumar ¹, J. S. Khamba ², S. K. Mohapatra ³

Affiliations
1 Dept. of Mechanical Engg., AKGEC, Ghaziabad, IN
2 Dept. of Mechanical Engg., UCOE, Punjabi University, Patiala, IN
3 Dept. of Mechanical Engg., TIET, Patiala, IN

Abstract

This paper reviews the fundamental principles of ultrasonic machining; the modes and mechanisms of material removal and the effect of operating parameters on the performance indices-material removal rate (MRR), tool wear rate (TWR) and surface roughness. The issues of production accuracy and precision in drilling deep holes have also been explored. A brief review on process application to the machining of titanium-considered as a tough material has also been presented. It has been concluded from the experimental study that ultrasonic machining could be applied effectively for machining titanium. When applied to titanium, ultrasonic machining results in low material removal rate (MRR), high tool wear rate (TWR) and low surface roughness.

Full Text