Abstract: Taking Landakin stoliczkana as the reference animal, ternary bionic coupling samples were designed according to the orthogonal design of experiment involving the morphology, the surface structure, and the material as test pactors. The samples were made on the substrate of the hard aluminum alloy LY12 or the steeel 45# with wearresistant coating. The erosive wear resistances of the samples were investigated by the sand blast test using the Al2O3 sand with partical size of 1000 μm as the erodent. The results indicated that the erosive wear resistance of the coupling sample with pitting structure is 18.7% higher than that of the sample without pits under the following test conditions: erosive time duration 180 s，sand impact angle 30°， impact distance 200 mm， blast air pressure 0.4 MPa. The optimal combination of the coupling sample characteristic factors are:hard aluminium alloy LY12 as the substrate, the morphology of the nonsmooth units is the regularly distributed rotundity pit with diameter 3 mm and spacing 6 mm, the coating is AL2O3+13%TiO2 with thickness of 100 μm.

Key words: bionics, bionic coupling, Laudakin stoliczkana, erosive wear, orthogonal design of experiment