Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Engineering
Surface Modification Of Titanium Foil Substrates In Experimental Solar Cells, Richard Nishimuro, Omar S. Es-Said
Surface Modification Of Titanium Foil Substrates In Experimental Solar Cells, Richard Nishimuro, Omar S. Es-Said
Mechanical Engineering Faculty Works
A case study involving surface smoothing of titanium foil was obtained from a solar cell research company. It was believed that the rougher surface of metals was responsible for low solar cell efficiency when using titanium foil rather than glass as a substrate. A method was needed to reduce the surface asperity height of the titanium foil from the existing 1 μm to less than 0.1 μm. Several methods were investigated. The recommended method was the use of an excimer laser, a laser powered by excited noble gas-halide molecules as a lasing medium.
On The Excessive Porosity In The Welds Of Ams 4975 Titanium Air Compressor Rotor Duct, Stefanie Roberts, Rachel Hoang, Laura Pate, Joseph Foyos, Richard Nishimuro, Omar S. Es-Said
On The Excessive Porosity In The Welds Of Ams 4975 Titanium Air Compressor Rotor Duct, Stefanie Roberts, Rachel Hoang, Laura Pate, Joseph Foyos, Richard Nishimuro, Omar S. Es-Said
Mechanical Engineering Faculty Works
This case study deals with the existence of excessive porosity in the welds of an air compressor rotor duct. The duct does not meet the testing criteria because the diameters of the pores in the weld exceeded allowable specifications. As such, the duct failed inspection for excessive pore diameter and shrinkage due to welding. At this point, the part was beyond repair, and it was scrapped. The possible causes of failure were analyzed, and it was concluded that the source of the problem was the welding technique.
On The Effectiveness Of Dry Film Lubricant Coatings In Reducing Automotive Valve Train Wear, Evan Benstead, Martin L. Smith, Joseph Foyos, Omar S. Es-Said
On The Effectiveness Of Dry Film Lubricant Coatings In Reducing Automotive Valve Train Wear, Evan Benstead, Martin L. Smith, Joseph Foyos, Omar S. Es-Said
Mechanical Engineering Faculty Works
The effect of three dry lubricants on automotive valve train wear resistance was studied experimentally. Scuffing wear occurs as the cam slides across the lifter face where the rotating motion of the camshaft is converted into the linear motion necessary to drive the cylinder head valves. This scuffing is caused by localized microscopic bonding between the skidding surfaces. It can be minimized by using dry film lubricant coatings to increase the boundary lubrication depth adjacent to the contact area. To compare valve train wear resistance in the laboratory, rotating cam lobes coated with dry lubricants--parkerization, spray-applied graphite coating, and brush-applied …