1. Z. Xu, et al., Method and apparatus for introducing normally solid materials into substrate surfaces, U.S. Patent No. 4,520,268 (1985).
2. Double layer ion metallic cementation;Xu;Trans. Met. Heat Treat.,1982
3. Surface alloying simplified;Xu;Adv. Mater. Processes,1997
4. Plasma Ni–Cr surface metallizing for A3 steel sheet;Fan;Heat Treat. Met.,1988
5. Age-hardening of surface age high speed steel on high carbon steel after plasma decarbonizing