搅拌摩擦加工细晶AZ91镁合金的加工特性.pdfVIP

Trans. Nonferrous Met. Soc. China 27(2017) 804−811 Machining characteristics of fine grained AZ91 Mg alloy processed by friction stir processing 1 1 1 1 1 G. V. V. SURYA KIRAN , K. HARI KRISHNA , Sk. SAMEER , M. BHARGAVI , B. SANTOSH KUMAR , 1 1 2 1 G. MOHANA RAO , Y. NAIDUBABU , RAVIKUMAR DUMPALA , B. RATNA SUNIL 1. Department of Mechanical Engineering, Rajiv Gandhi University of Knowledge Technologies (AP-IIIT), Nuzvid 521202, India; 2. Department of Mechanical Engineering, Visvesvaraya National Institute of Technology, Nagpur 440010, India Received 7 April 2016; accepted 29 October 2016 Abstract: AZ91 Mg alloy was considered and friction stir processing (FSP) was adopted to achieve grain refinement to investigate the effect of grain size and secondary phase on machining characteristics during drilling at various speeds and feeds. Super saturated AZ91 Mg alloy was obtained after FSP and the grain refinement was achieved from (166.5±8.7) µm to (21.7±13.5) µm. Surprisingly, hardness reduced for FSP AZ91 Mg alloy (88.95±6.1) compared with AZ91 alloy (108.2±15.6), which was attributed to the reduced secondary phase. However, the mean cutting force for FSP-treated (FSPed) AZ91 Mg alloy was marginally increased. The edge damage of the drilled holes was lower for FSPed AZ91 Mg alloy compared with unprocessed A