Abstract:
A hard-faced welding is an important method for improving a surfaces property of the
parent metal.This method is successfully introduced for repairing an agricultural part surface that is
deteriorated from a long service.However, theoptimizationof welding process parameters has not
been fully understood. This researchaimed to study an influence of alayer number of the flux-cored
arc welding hardfacing on the welded properties of the JIS S50C carbon steel.
This experiment used the JIS S50C carbon steel plate which was rectangular sized of 150
mm. length, 100 mm. width and 20 mm. thickness.The sample plate was flux-cored arc welded
(FCW) using the welding process parameters i.e. the welding current of 170-230 A. and a hardfaced
layers of 1-3 layers.The welded specimen was mechanically prepared and investigated for the
hardness, wear resistance and macro-microstructure of the weld.
The experimental results can be summarized as follows.Increasing of FCW welding
current affected to increase hardness and increase wear resistance of the material. The hard-faced
metal sample without the welded buffer layer showed higher hardness and higher wear resistance
than the one with welded buffer layer. It was found that the optimized welding parameters were the
welding current of 210 A, the welded without a buffer layer and the hard-faced layer of 3 layers.
This produced a hard-surfaced of 755 HV hardness, the weight loss of 0.02% and the absorbed
energy of 7 J. The increment of hardness and wear resistance was caused by increasing chromium
and vanadium amounts in the welded layer.