Abstract. Surface modification of cast iron by pulsed laser deposition was carried out to obtain a higher wear-resistant surface. The surfaces of cast iron samples were melted by a pulsed Nd:YAG laser with and without deposition of molten metal (Mo, W and Ni) particles. The metal particles to be deposited were generated by the irradiation of metal targets using another pulsed Nd:YAG laser. Without deposition, a fine martensite-ledeburite microstructure with hardness of about 1000 HV was formed by melting a cast iron sample. With deposition of Mo or W, complex carbides around martensite islands were formed by melting the surface; a hardness of 1000-1150 HV was obtained. When Ni was deposited, on the contrary, the obtained hardness of the melted layer ranged from 500 to 900 HV; the hardness depended on the amount of Ni deposit. Insread of the formation of martensite, residual austenite was formed by the Ni deposit. Wear charactesitics such as the correlation between hardness and wear resistance were investigated by performing sliding tests on the surface-modified cast iron samples.

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