[1] L Thivillon, P H Bertrand, B Laget, et al.. Potential of direct metal deposition technology for manufacturing thick functionally graded coatings and parts for reactors components[J]. Journal of Nuclear Materials, 2009, 385(2): 236-241.

[2] K I Schwendner, R Banerjee, P C Collins, et al.. Direct laser deposition of alloys from elemental powder blends[J]. Scripta Materialia, 2001, 45(10): 1123-1129.

[3] C L Atwood, M L Griffith, M E Schlienger, et al.. Laser engineered net shaping (LENSTM): A tool for direct fabrication of metal parts [C]. Processing of the Laser Materials Processing Conference Section A-ICALEO′1998, 1998, 16-19: E-1.

[4] Song Jianli, Li Yongtang, Deng Qilin, et al.. Research progress of laser cladding forming technology[J]. Chinese Journal of Mechanical Engineering, 2010, 46(14): 29-39.

[5] Wang Xuyue, Wang Yanfei, Jiang Hao, et al.. Laser cladding forming of round thin-walled parts with slope angle[J]. Chinese J Lasers, 2014, 41(1): 0103006.

[6] T Gareth, Mark Pridham. Improvements to laser forming through process control refinements[J]. Optics & Laser Technology, 1998, 30(2): 141-146.

[7] G J Bi, A Gasser, K Wissenbach, et al.. Investigation on the direct laser metallic powder deposition process via temperature measurement [J]. Appl Surf, 2006, 253(3): 1411-1416.

[8] Zhu Gangxian, Li Dichen, Zhang Anfeng, et al.. The influence of laser and powder defocusing characteristics on the surface quality in laser direct metal deposition[J]. Optics & Laser Technology, 2012, 44(2): 349-356.

[9] H Dongming, R Kovacevic. Sensing, modeling and control for laser-based additive manufacturing[J]. International Journal of Machine Tools and Manufacture, 2003, 43(1): 51-60.

[10] Liu Jichang, Li Lijun. In-time motion adjustment in laser cladding manufacturing process for improving dimensional accuracy and surface finish of the formed part[J]. Optics & Laser Technology, 2004, 36(6): 477-483.

[11] G Bi, A Gasser, K Wissenbach, et al.. Characterization of the process control for the direct laser metallic powder deposition[J]. Surface and Coatings Technology, 2006, 201(6): 2676-2683.

[12] Gao Shiyou, Li Jian, Li Chenguang, et al.. Research on the variation regularity of single laser tracks cross- section morphology during laser cladding[J]. Chinese J Lasers, 2013, 40(5): 0503010.

[13] Wang Xiaojia, Gao Jun, Wang Lei. Survey on the laser triangulation[J] . Chinese Journal of Scientific Instrument, 2004, 128(s2): 601-604.

[14] Wang Shaoqing, Zhuang Baohua. Rebuilding principle formula of optical triangulation method of displacement measurement in view of the Lambert theory[J]. Acta Optica Sinica, 1996, 16(12): 1802-1808.

[15] Dong Ling, Yang Xichen, Lei Jianbo. Off-line automatic programming research of laser remanufacturing robot based on machine vision[J]. Chinese J Lasers, 2013, 40(10): 1003006.

[16] J Mazumder, D Dutta, N Kikuchi, et al.. Closed loop direct metal deposition: art to part[J]. Optics and Lasers in Engineering, 2000, 34(4): 397-414.

[17] A Heralic′ , A K Christiansson, B Lennartson, et al.. Height control of laser metal- wire deposition based on iterative learning control and 3D scanning[J]. Optics and Lasers in Engineering, 2012, 50(9): 1230-1241.

[18] Liu Jianzhuang, Li Wenqing. The automatic thresholding of gray- level picture via two- dimensional OTSU method[J]. Acta Automatica Sinica,1993, 19(1): 101-105.