外文翻译---材料制备机械设计理论中的新趋势和新问题-机械设计(编辑修改稿)

外文翻译---材料制备机械设计理论中的新趋势和新问题-机械设计(编辑修改稿)内容摘要：

chine (1) To have the ability to produce and bear extraordinary physical field and transmit extraordinary energy flow with the aim of providing extraordinary physical circumstances necessary for new concept material processing. For example ,high gradient temperature field with the speed of cool down of work interface which exceeds 104～ 106 K s 1 , line wave and pulse plex exerted in solidifying deforming area , super strength contact stress field of material forming interface ,turbulent flow field of molten metal with very big flakiness ratio ,low frequency magic field with random frequency ,microwave field for powder metal heating ,ultrasonic field for large volume solidifying ,etc. are applied. (2) To have the ability to work in critical state so that high stability and ideal performance of processing machine is ensured under the circumstance of reinforced technological condition and multi field coupling operation. For example ,chatter suppressing capability of fast ultra thin rolling under the condition of boundary lubricating state,the capability of self excited vibration suppressing under the condition of special friction state ,synergism stability and disturbance stability of flexible connecting parallel shaft with multi driving system ,etc. are ensured. (3) To have the ability to accurately control the material processing in order to obtain low loss ,high efficiency and high quality of material processing. For example , super high accuracy on line monitor of products form ,on – line monitor and on line adjustment of products texture and properties ,precision coordination control of multi procedure , on line monitor of micro orientation of metal plastic deformation ,etc.,are ensured. Some products accuracy index may be enumerated as follows : dimensional accuracy ing to m , microstructure uniformity to crystal lattice ,strength error to MPa ,etc. In short ,only by new concept material processing machine with extraordinary function being designed and made , can special function material be processed. 3 Science Problems and Study Contents of Metal Material Processing Machine Under the Circumstance of Extraordinary Physical Field In view of these facts and background mentioned above ,several new research topics can be advanced as follows. 3. 1 Coupling Heat Transfer Mechanism of Multi Phase Interface Temperature Stress Field A brand new microstructure can be obtained through continuously large deformation and fast solidifying when melting metal is in critical state of liquid solid. At this very moment ,high density heat flow and dynamic heat resistance are present in material processing circumstance. A basic theory problem of designing this kind of machine is to study mechanism of heat transmittance and energy conversion ,and to establish mathematical model . 3. 2 Friction Constraint Mechanism of Plastic Flow Interface of Material Processing Machine The coupling between operation mechanism and workpiece is very plicated because plastic flow is present in processing interface. The interface state , determined by velocity , load thermodynamic process , elasticity of operation mechanism ,plasticity of workpiece ,dynamic behaviour of interface sticking sliding and p。