【正文】 Load With regard to statically indeterminate structure ,load distribution of constraint point is determined by deformation patibility condition. However ,concerning some plane large size statically indeterminate structure with sliding degree of freedom in third dimension ,load distribution can not be determined by deformation patibility condition. Thus new theory basis will be provided by analyzing of contact behaviour and mechanism of sliding pair (such as creep ,force of friction ,integral deformation patibility condition ,etc) . 3. 5 Coupling Mechanism and Stability of Multi Physical Fields in Material Processing Systems In the wake of system function being more and more diversified , conventional technology limits in material processing machine is being broke through unceasingly ,system structure also bees increasingly plicated ,and system performance bees increasingly multi causal . For example ,any instantaneous state of roller in fast rolling mills is affected by elastic deformation ,plastic flow ,heat transfer process , hydro dynamic lubrication process ,interface physical chemistry molecular state and so on . In addition ,electromechanical coupling in processing system have already gone beyond conventional concept ,for instance ,some singular point phenomenon (such as micro variable can be transformed into macro variable) ,are present ,thus roller operation instability may be led by perturbation[8 ] . Therefore ,this subject will study the interaction mechanism of multi physical field and the influence on processing system stability and processing material quality started with analysis of micro state of executive body. 6 3. 6 Multi Technology Integration and Coalescence of Accurate Control The material processing machine ,which operate under the circumstance of extraordinary physical field ,is a plicated large scale system ,and some parameters of the system vary on feasible field boundary 。s 1 ,the deformation pressure rises up to 300 MPa ,accuracy of dimension up to ,accuracy of shape up to 0. 1 I ,strength accuracy es up to MPa. For these reasons ,it is necessary for material processing machine design theory to integrate and coalesce ingeniously correlative frontier science and technology to create and produce some new concept material processing machine with following functions. 3 2 Due Functions of New Concept Material Processing Machine (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 procession machine 。and thereafter a brief discussion is given. Keywords: interface。 1 New Trends and Problems in Material Processing Machine Design Theory WANG Ailun ,DUAN Jian ,HUANG Minghui ,ZHONG Jue (College of Mechanical amp。 Electronic Engineering , Central South University ,Changsha 410083 ,Hunan China) Abstract : Based on reviewing the historical background, prospecting for the development trend ,analyzing the plicacy and mechanism and summing up some achievements and experiences in scientific research , several new problems and the possible direction of development i