National Natural Science Foundation of China(51301211,21271188);the Foundation of Laboratory of Ultra Precision Manufacturing Technology of CAEP(ZZ13005);Research Foundation of CAEP(2010A0302013);the China Postdoctoral Science Foundation(2012M521541);the State Key Laboratory of Powder Metallurgy(20110933K);the Open-End Fund for Valuable and Precision Instruments of Central South University(CSU2013016)