65results about How to "Promote heterogeneous nucleation" patented technology

The invention relates to an amorphous alloy inoculation method for treating cast aluminum alloy. The amorphous alloy inoculation method for treating the cast aluminum alloy comprises preparation of inoculant and amorphous inoculation treatment. The technological parameter of the inoculation treatment is as follows: adding a prepared amorphous thin strip into aluminum melt before the aluminum is cast, the temperature of the aluminum melt is from 750 DEG C to 770 DEG C; the added amount of the amorphous inoculant is 0.05-1.0 wt.% of the weight of the aluminum; the treating time of inoculation is 15-600 seconds; an auxiliary machinery stirs for 0-300 seconds; and auxiliary ultrasound shocks for 0-180 seconds. The inoculant utilized by the amorphous alloy inoculation method is multivariate amorphous alloy including Zr series, Ni series, Cu series, Al series, Ti series and the like, precious metal is not contained, and cost is lower. The inoculant is in a thin-strip shape, can be dispersed in the melt uniformly and conveniently, the actual receiving ratio of modificator is high, tissue after refining is uniform, the time of modification treatment and alloy solidification are greatly shortened, and production efficiency is high. Moreover, the amorphous alloy inoculation method for treating cast aluminum alloy is applicable to large-batch continuous production of the amorphous alloy for a long time.

The invention discloses a preparation method of foamed polypropylene beads. The method comprises the following steps that 1, polypropylene resin, an active filler and auxiliaries are added into a high-speed mixing machine and mixed to be uniform at the temperature of 10-20 DEG C, and a polypropylene foaming material is obtained; 2, the polypropylene foaming material is added into a triple-screw extruder, plastification and mixing are conducted, a supercritical fluid is injected, the mouth mold pressure is controlled to be 5-25 MPa, the mouth mold temperature is 110-160 DEG C, instant pressure release is conducted through a mouth mold, foaming is conducted, and super-fine hole foamed polypropylene is obtained; 3, super-fine hole foamed polypropylene is subjected to mold surface water-ring hot-cutting granulation, drying and sieving, and the foamed polypropylene beads are obtained. The method is low in production cost, high in capacity, safe and environmentally friendly, no foaming agent decomposed residue exists in the prepared foamed polypropylene beads, secondary foaming can be conducted, the foaming ratio can be adjusted, the rebound resilience of a finished product is high, decomposing and recycling are easy, and the foamed polypropylene beads can be widely used in the fields of plastic packaging, transportation industry, military aerospace, office supplies and the like.