Nickel Alloy Essay

Table 1.1 Classification of the nickel alloys [19]

Sr no Classification of Nickel Alloys Group Characteristics Group Name Alloys of Nickel
1 Caustic alkali, chemical and Electrical Applications. Lowest strength and Work Hardening. Hardenable by Cold working A Alloy 200
Alloy 201
Alloy 205
Alloy 212
Alloy 222
2 Contains Ni+ Cu and Ni+ Fe for acidic, corrosive and electrical applications, Higher strength than Group-A. Best machining is obtained in cold drawn and stress relieved conditions B Alloy 400
Alloy 401
Alloy 450
Alloy 36
Alloy K
Alloy MS 250
3 Contains Ni+Cr, and Ni+Cr+Fe for acidic and high temperature corrosion applications. These alloys are best machine in cold drawn or stress relived conditions. C Alloy 600
Alloy 690
Alloy 601

Heat Generation in Machining
There are four components that carry the heat that is generated in machining. They are cutting fluids, chips, work piece and tool. There are numerous approaches used by the metal cutting researchers. As indicated by Silva M. B. et al.,1999 [21].
In any machining process there is a continuous plastic deformation of the layer being cut. In addition to this there is friction between the tool-chip and tool-work interfaces. This results in high amount of heat generation in machining. Yildiz Y. et al. 2008 [20] The heat generation has a considerable effect on the quality of part produced as an output of machining.
Silva M. B. et al.,1999 [21] stressed that in machining, heat is generated due to the plastic deformation of layer being cut and as well as due to the frictional forces created between the tool/chip and tool/work interface.
Hong S. Y.et al.,1999 [14] defined the role of cryogenic cooling in metal cutting, to remove the heat effectively from the cutting zone, hence lowering cutting temperatures, altering the frictional characteristics at the tool/chip interfaces, modifying the properties of the tool and the workpiece material Below is given an account of the heat generation and temperature distribution in

There are a lot of applications of cryogenic treatment or processing to enhance wear resistance and strength of tool materials from end mills to guillotine knives in industry [29]. But the effect of the cryogenic treatment on cutting performance is not known for all of the machining operations and cutting conditions. . It is alos noted that there is not much difference between the hardness of the cryogenically treated and untreated High Speed Steel Tools. [28]. But one study carried out on AISI M2 High Speed Steel showed an improvement in the hardness and toughness [30]. Now it is eveident that the difference between these two observations could indicate the difference between the methods of the cryogenic treatment.

Gill et al. [46] state that for cryogenic treatment there are three parameters are important that affect the micro structure and the properties of the tool materials. They are
• Cryogenic Temperature.
• Duration for which the treatment is carried