Resistance spot welding (RSW), generally which is one of the most often used to joint metal plate in the automotive and aviation industries. RSW welding process involves electrical, thermal mechanical, metallurgy, and complex surface phenomenon. Unlike the other welding processes, weld joint formation in RSW process occurs very quick (in milli-seconds) and took place between the workpieces overlap each other. Welding simulation allows visual examination of the weld joint without having to perform an expensive experiment. Weld nugget size is the most important parameter in determining the mechanical behavior of welded joints in RSW process. The quality and strength of the weld joint in RSW process is predominantly determined by the shape and size of the weld nugget. Simulation modeling of RSW process performed using ANSYS Parametric Design Language (APDL) module based on the finite element method (FEM), embedded in ANSYS Workbench. Electrical and transient-thermal interaction was developed to study the weld nugget growth on resistance spot welding of aluminum A1100 metal plate with a thickness of 0.4 mm respectively. Weld nugget diameter can be well predicted by using this simulation model from the temperature distribution during the welding process. Welding is performed by varying the weld current (1 kA and 2 kA) and the welding time for each electric current, which are start from 0.5, 1.0, and 1.5 cycle time. Nugget diameter for each of the welding parameters from the simulation modelling were 4,276 mm, 4,372 mm, 4,668 mm, 5,616 mm and 5,896 mm. Weld expulsion occurred for the specimen with welding current 2 kA and welding time 1.5 cycle time, characterized by the decreasing of the tensile-shear strength of the specimen.

Minimum quantity lubrication (MQL) is the most used recent method in the milling process that is economical and environmentally friendly. The MQL method can reduce the temperature during the milling process. The high temperature that occurs in the carbide tool will affect the tool’s life. The use of cooling fluid is a common method to reduce high temperatures. However, the remaining cooling fluid has an impact on the pollution of the environment. Therefore, in this study, a novel approach for a cooling system based on the combined MQL method and fan cooling device was introduced and called an MQL Chip fan. The effect of the MQL Chip fan on the temperature, tool life, and surface roughness was investigated. The Taylor equation was used to calculate tool life based on temperature data from an experimental investigation. Subsequently, the quality inspection was conducted by using a surface roughness tester. The spindle speed and depth of cut have proven to make a great impact on the peak temperature, but, there is an optimal point where spindle speed made a turbulence and the tool had a passive cooling system. The utilization of the MQL Chip fan has decreased temperature by more than half at a medium speed of 2241 rpm and made a high contribution for low-speed processing and only a slight contribution for high-speed processing. Based on Tool Life prediction, 3600 RPM with a 3 mm depth of cut has more efficient performance compared to 2241 rpm with the same depth of cut. The utilization of the MQL Chip fan contributes significantly to the roughness value; the Ra value decreased from 1.374 μm to 0.461 μm. It has been proven that the utilization of an MQL Chip fan in the milling process reduces temperature and also increases the tool life.