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The abrasive testing machine with operation process similar to the pelleting circular mold was used, taking the alfalfa grass powder as abrasive material. The influences of alfalfa powder on the abrasive properties of four kind of metal materials were examined, by measuring the rigidity and chemical components of the abraded surfaces and analyzing of the microstructures and surface morphologies of the abraded surfaces. It is shown that the abrasive quantities of four samples as below are orderly increased, 3Cr13, 9SiCr, 45# steel, and HT200, some physical and chemical changes take place on the abraded surfaces, and “the soft abrasive wear” is accompanied by “the hard abrasive wear” feature due to the micro-cutting and strain fatigue.