The popular use of ball bearing for general industrial application can generally be associated with the late nineteenth century. With the increased usage and the increased sophistication of mechanical design came to necessity to predict their endurance capability.
In this project an Effort has been put to analyze the deep groove ball bearing using finite element analysis the stress levels or displacement behavior of ball bearing.
1.1HARDNESS IN STEEL
The property of hardness in steel, especially in ball bearing plays a major role in improving the wear resistance and life of bearing the hardness of steel is increased by the martensite content present in them
The martensite formation is not an easy process involving heat treatment cycles. The heat treatment cycles vary for various steels.
The martensite transformation occurs only when the austenite is super cooled by rapid cooling (quenching) to low temperature at which diffusion possesses become impossible. In contrast to the pearlite and intermediate transformation, the martensite transformation is of diffusion less nature i.e. it is not accompanied with diffusive displacements of carbon and iron in the rearrangement of the precipitate of carbon from the solution. This leads to the distortion of the cubic lattice that makes it tetragonal.
The main feature of the martensite transformation, distinguishing it from transformation that progress by ordinary crystallization kinetics, is the fact that is has no phase of nucleation and growth of crystals of the new phase.
The transformation is accomplished by a shift, i.e.an ordinary cooperative transfer of atoms from the austenite to martensite. The atoms are not interchanged in re arrangement of the lattice, but, are only displaced by distances not exceeding the inter atomic ones. The material crystals are shapes like plates narrowed at the edges
2.1 THERMAL STRESS ANALYSIS OF CRYOTREATED MULTIPOINT
CUTTING TOOLS – AN FEM APPROACH(K. SHANMUGAM AND D.
Heat treatment is a process which greatly improves performance of tool. Cryogenic treatment is a process that helps to improve some of the desirable characteristics of tool steel due to
1. Retained as a structure getting transformed into martensite, a hard structure. 2. Fine precipitation of alloying carbides.
The present work concentrates on analyzing the residual stresses. The finite element analysis is carried out for tool steels incorporating the temperature dependent material properties and bilinear kinematic hardening procedure. The result shows that the surface stresses are almost compressive. And M2 steel milling cutter indicated that the thermal equilibrium is reached at 4000 seconds. The time history evinces that the final maximum deformation for multi-point tool is 0.605 mm. 2.1 CRYOGENIC TECHNICAL JOURNAL:
Fanju meng, Kohsuke Tagashira, Ryo Azuma and Hideaki sohma from Muroran Institute of Technology, Department of Mechanical Engineering, Mizumoto, Japan have done cryogenic technical study. The wear resistance of alloy tool steel after cold at 223 K and after cryogenic treatment at 93 K has been investigated. The wear resistance of steels after cryogenic treatment is superior to that of cold treatment. The effect of cryogenic treatment is superior to that of cold treatment. The effect of cryogenic treatment on the microstructure were also studied by means of X-ray diffraction and transmission
electron microscopy methods.
Unlike cold treatment, cryogenic treatment includes preferential precipitation of fine
n-carbide instead of e-carbides. These fine carbide particles enhance the strength and toughness of the martensite matrix and then increase the wear resistance. The formation mechanism of fine n-carbide is analyzed.
3.2 CRYOGENIC PROCESSING IN CRYOTRON:
Cryotron Ltd is an industrial services and...
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