Nthawi zambiri, pamwamba ndi kumapeto kwa mphete yoyamba ndi chrome-yokutidwa, ndipo mphete zina za pistoni zimathanso kukhala zokutidwa ndi chrome. Mphete zazikulu za pistoni za injini ya dizilo sizimakutidwa ndi chrome, ndipo zomangira za silinda zimakutidwa ndi chrome. Pakalipano, mphete ya pistoni yopangidwa ndi chrome-ceramic yapangidwa, ndipo kuyesa kumasonyeza kuti kuvala kumakhala kosakwana theka la mphete ya pistoni ya chrome, ndipo kuvala kwa silinda yofananira kumachepetsedwanso.

Wosanjikiza wopopera wa Molybdenum amakana kuvala bwino, kukopeka komanso kukana kwa silinda kuposa plating ya chrome. Chovala chachitsulo cha chrome chokhala ndi silinda yachitsulo ndi mphete ya pistoni yopopera molybdenum zitha kupanga zosemphana bwino.

Zosanjikiza zolimba zomwe zimagwiritsidwa ntchito kwambiri pa mphete za piston ndi aluminium oxide, titanium oxide ndi chromium oxide, makamaka zokutira za aluminium titanate.

Njira yokhazikitsira ion imaphatikiza zinthu zamakemikolo osankhidwa kukhala mtolo mu liner ya silinda ndi malo a mphete ya pistoni. Wosanjikiza jekeseni wa ion amaphatikizidwa ndi pamwamba pa silinda ya silinda ndi mphete ya pisitoni, ndipo alibe mphamvu pang'ono pakuuma kwapamwamba komanso kulondola kwake. Pali makamaka plasma plating TiN diffusion wosanjikiza, pamwamba ion plating CrN hard film, osowa lapansi ion carburizing ndi zina zotero. Zoyeserera zikuwonetsa kuti kuzimitsa ndi kutenthetsa mphete ya pisitoni kenako ndikuyika nitridi pamwamba pa ma ion apansi osowa kumatha kusintha kwambiri kukana kwa mphete ya pistoni ndikutalikitsa moyo wake wautumiki.

Pamwamba kondomu mankhwala ndi mankhwala kupanga zitsulo pawiri filimu pamwamba chitsulo, zitsulo ndi ufa zitsulo zipangizo kuchita kudziletsa mafuta. Pali makamaka mapangidwe a filimu yopangira mankhwala a nthunzi phosphating ndi mapangidwe a filimu ya alkaline oxidation treatment, omwe amagwiritsidwa ntchito popanga mphete za pistoni ndi ma silinda a injini zazing'ono zoyatsira mkati. Kuphatikiza apo, nitriding yamadzimadzi ndi nitriding yofewa imathanso kupititsa patsogolo kukana kwa ma silinda achitsulo.

Kukaniza kuvala kwa mikangano kumakhudzidwa ndi zinthu zosiyanasiyana, kotero kuti pamwamba pake amathandizidwa ndi kukana kuvala kangapo. Mwachitsanzo: njira yothetsera moto ndi sulfurizing, kuzimitsa carburizing ndi sulfurizing, nitriding yofewa ndi sulfurizing, nitroxide ndi kuphatikiza kwa chrome plating ndi molybdenum spray.