Ce-Y modified aluminum coatings were prepared on DZ125 alloy by pack cementation processes at 950 ℃for 2 h.The microstructure and formation mechanism of the coatings were investigated.The friction-wear properties of the DZ125 alloy and the coatings were analyzed comparatively at 20 ℃

300℃ and 600℃.The results show that the prepared Ce-Y modified aluminum coatings with a thickness about 125μm exhibit compact

which mainly consist of Al

3

Ni

2

Al

3

Ni and Cr

7

Ni

3

.The Ce-Y modified aluminum coatings have the more superior anti-friction behavior than DZ125 alloy with sliding at 20 ℃and 600 ℃

while the opposite results can be observed with sliding at 300℃.Sliding at 20℃

the wear mechanisms of DZ125 alloy are characterized by delamination wear and slight abrasive wear

while those of the Ce-Y modified aluminum coating are surface scratches.The wear mechanisms of DZ125 alloy are turned to be delamination wear

adhesive wear and abrasive wear

and those of the Al-Ce-Y coating are characterized by delamination wear and abrasive wear when the sliding temperature is increased up to300 ℃.Sliding at 600℃

the dominated wear mechanisms of both substrate and the coating can be concluded as delamination wear and abrasive wear.