Investigation of inclusion casting, sand blasting and embossing methods to prepare engine cylinder bore surface for frictional and wear improvement

• Main Author: Kong, Chung Hwa
• Format: Thesis
• Language: English
• Published: 2021
• Subjects: T Technology (General); TA Engineering (General). Civil engineering (General)
• Online Access: http://umpir.ump.edu.my/id/eprint/34927/1/Investigation%20of%20inclusion%20casting%2C%20sand%20blasting%20and%20embossing%20methods%20to%20prepare%20engine.ir.pdf; http://umpir.ump.edu.my/id/eprint/34927/
• Institution: Universiti Malaysia Pahang

Frictional losses between the piston rings to cylinder bore surface is one of the major sources of mechanical losses in internal combustion engines (ICE). Traditional plateau honing produces a relatively rough cylinder bore surface with many valleys for oil retention and plateaued surfaces that usually have micro roughness that cause mechanical friction to act as a bearing surface. A smooth polished dimpled surface is more ideal to achieve low friction and wear in an ICE. The objectives of this study are to produce samples that have smooth plateau surfaces and have oil retaining dimples via sandblasting, embossing and inclusion casting. Then these samples were characterized to study the results of variable grit sizes of the sandblast, emboss and graphite powder to the size of the dimples as a result of the roughness of the samples produced. Finally, the samples with the best surface characteristics are selected for wear testing and the results are compared to a conventional plateau honed sample. Hypereutectic aluminium SC114A samples were prepared by embossing with sandpaper, sandblasting with silica sand and inclusion cast with graphite powder of varying sizes. The samples are then buffed and polished to create smooth flat plateaus and the friction and wear are evaluated in this study using an oscillating wear tester (OWT). The samples were also characterized using a surface profilometer and Scanning Electron Microscope (SEM). From the surface characterization, it was determined that the samples embossed with #480 grit sandpaper, sandblasted with #320 sieve silica sand and inclusion cast with #270 grit graphite powder had the desired properties to be tested further. It was found that surface sandblasted with #320 silica sand with a reduced coefficient of friction (μ) of 18% at 300 RPM and 6% at 1200 RPM. Even after 900,000 cycles of accelerated wear testing, the μ of #320 sandblasted sample remains 5% lower than the conventional plateau honed sample. This shows that a surface with lower friction and improved wear can be produced using one of the alternative methods investigated in this study.