CHAPTER 1
INTRODUCTION
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.
1.2MARTENSITE TRANSFORMATION
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.
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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
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CHAPTER 2