This article describes the benefits that can be achieved by using thermal spray on particular engine parts of an automobile. These include improvement in fuel consumption, wear resistance and bonding, and reduction of oil consumption, exhaust heat loss, and cooling heat loss. Typical engine parts are cylinder blocks, cylinder bores, cast iron cylinder liners, piston rings, connecting rod bearings, turbochargers, engine valve lifters, exhaust system parts, and oxygen sensors. The article also describes the benefits of using thermal spray on transmission parts such as synchronizer rings and torque converters.

Lapping is the lower-pressure, lower-speed, and lower-power application of the use of fixed abrasives. This article begins with a discussion on the process capabilities of lapping and reviews the selection of abrasive and vehicle for lapping. It describes the methods of lapping outer cylindrical surfaces, namely, ring lapping, machine lapping between plates, centerless roll lapping with loose abrasives, and centerless lapping with bonded abrasives. In addition, the article discusses the methods employed for lapping of outer surfaces of piston rings, crankshafts, inner cylindrical surfaces, flat surfaces, end surfaces, spherical surfaces, balls, spring like parts, and gears. It also reviews the problems in flat and end lapping. The article concludes information on the use of lapping in accelerated wearing-in process for matching and aligning components of bearing assemblies.