Casting defects in investment casting parts such as shrinkage porosity（hole） were commonly eliminated by setting gates or adding riser at hot spot position to form effectively feeding channel during cooling and solidification process

obtaining investment castings with excellent quality.The main principle of processing design is related to casting structure.Environmental effects on cooling and solidification process can be little considered to improve the design sketch with saving cost and more quality.Hot iron and chill are applied in the design to improve the quality of investment castings from cooling environment

and desirable application effects are presented.