Abstract
The bearing is a machine element that plays an important role in rotating the shaft of a machine while supporting its weight and load. Numerous bearings have been developed to improve durability and life, depending on the functions and operating conditions in which they are desired. White metal is one of method to improve durability that is soft and bonded to the inner surface of the bearing to protect the bearing shaft. Currently, the centrifugal casting process is used as a white metal lamination method, but it involves problems such as long processing times, high defect rates and harmful health effects. In this paper, a laser cladding treatment is applied to bond powdered white metal to SCM440 alloy steel, which is used as bearing material in terms of replacing the risks of a centrifugal process. In order to understand whether laser cladding is a suitable process, this paper compares the mechanical properties of white metal produced on SCM440 alloy steel by centrifugal casting and the laser cladding process. The laser power, powder feed rate and laser head speed factors are varied to understand the mechanical properties and measure the hardness using micro Vickers and conduct field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and friction testing to understand the mechanical properties and surface characteristics. Based on the results, the hardness values of the cladding (white metal) layer ranged between 24 and 26 HV in both the centrifugal casting and laser cladding methods. However, the hardness of the white metal produced by laser cladding at about a depth of 0.1 mm rose rapidly in the cladding process, forming a heat-affected zone (HAZ) with an average hardness value of 200 HV at a laser power of 1.1 kW, 325 HV at 1.3 kW and 430 HV at 1.5 kW. The surface friction testing results revealed no significant differences in the friction coefficient between the centrifugal casting and laser cladding methods, which allows the assumption that the processing method does not significantly influence the friction coefficient.
Highlights
The bearing is a machine element that plays an important role in rotating the shaft of a machine while supporting its deadweight load
This study aims to determine the mechanical properties of the mounted test specimens under different conditions by analyzing the hardness, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and friction test results and identifying the optimal laser cladding conditions for white metal cladding
When comparing the hardness values in the cladding layer, the laser cladding process hardness value was close to the centrifugal casting process hardness value, so it seemed that it could be replaced
Summary
The bearing is a machine element that plays an important role in rotating the shaft of a machine while supporting its deadweight load. It is an elementary machine component used in all industries, including leading and future industries. Durability is an important requirement for a bearing, whose service life is greatly affected by the vibration and wear between the shaft and bearing surfaces and fatigue damage [1]. Given the close association between the service life of a bearing and its durability, the durability is an important engineering parameter of a bearing which is directly related to its reliability in terms of the maintenance and repair of the entire machine. Intensive studies are being conducted to establish methods to enhance the durability, such as techniques for the homogenization and surface treatment of the bearing material [2]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
