Comparative study of techniques for wear minimisation of engine parts

In order to increase wear resistance investigations of locomotive engine parts on the comparison of different techniques for surface treatment were undertaken and compared with respect to their best fit for purpose. Base of the development was to improve the resistance of cylinder liners against abrasive wear in the region of the upper dead centre as well as of piston ring grooves against wear and deformation. Techniques compared are laser transformation hardening and laser-assisted alloying. During surface characterisation and wear tests alloyed surfaces have shown a better integrity of the surface and slightly smaller abrasion. The break out of Steadite grains observed in the hardened surfaces will increase the capacity of lubricant storage and improve failsafe running functions. This effect makes transformation hardening the preferred technique for cylinder liner treatment. For the piston ring grooves careful analysis has proven the equivalence of the techniques. For reasons of simplicity in production also transformation hardening will be preferred. However, the balance will turn according to the field tests of the components which are currently under appraisal.