摘要:A layer of SiC/Al composite on the Al alloy casting surface has been obtained byusing vacuum technology.The microstructure and interface phenomenon of SiC/Al has beenstudied and the results show that SiC particles distrubute evenly on the matrix and combine withthe matrix metal very well.
摘要:A study of the effect of metallurgical factors under nonvacuum condition on thestructures and properties of Monel metal shows that tight covering and effective refining are indispensable means for lowering the gas contents, reducing harmful inclusions, raising mechnicalproperties and corrosive resistances of the alloy;and that the modification processing is an importaut method for refining the fining grains, for eliminating flourishing dendrits and for reducingshrinkage porosities.
摘要:The difference between fusible plaster mold and foaming plaster mold is discussedand an allaround suveying of the features of foaming plaster mold is made, and the facilities andmethods for permeability measuring are introduced. It is proposed that there are three criterionsfor evaluating the qualities of foaming agents. An ideal agent has been obtained by experiments.The relations among the agitating time,speed and foaming increament are established. Foamingplaster molds with foaming rate over 50%, with permeability up to 6 cm/min and compressivestrength up to 0. 8 MPa can be obtained according to the proposed technical regulations.