高熔点合金半固态熔体的感应炉保温制备  

Preparation of Semi-solid Low Alloy Steel Slurries with Induction Furnace at Holding

作　　者：张励忠[1] 李海开[1] 胡远猛[1] 韩淑霞[1] 肖黎明[1] 

机构地区：[1]北京交通大学

出　　处：《特种铸造及有色合金》2006年第6期362-365,共4页Special Casting & Nonferrous Alloys

基　　金：北方交通大学"十五"科研计划重大项目(230-12)

摘　　要：研究了中频感应炉在近液相线保温制备低合金钢半固态熔体的方法。通过研究不同保温条件下的水淬组织和空冷组织,掌握了保温温度、保温时间及加热方式对组织的影响规律。在大过冷度和大过热温度下,熔体内不易形成晶坯(准固相原子团簇)和游离晶,水淬组织粗大,而在近液相线温度(1508℃)下,熔体内易形成大量晶坯并演化为游离晶均匀分布于熔体内,它们能在凝固时显著细化、匀化晶粒,使水淬组织细小、均匀,即使在空冷条件下,这种细化机制也起作用。由于中频感应炉的电磁搅拌作用,在近液相线温度短时保温就可孕育出相当数目的游离晶,并能在随后的保温过程中保持游离晶的形态和数目,保温时间为5～50min的水淬组织没有显著变化。A simple and feasible method of preparing of semi-solid low alloy steel slurries at near liquidus temperature with medium-frequency induction furnance at holding is described. The effects of holding temperature, holding time and heating ways on the microstructure of the slurries are understood by observing water-quenched and air-cooled microstructures at different holding conditions. Few free nucleus are formed in the melt under the condition of large superheat or supercooling, resulting in coarse water-quenched microstructure, while amounts of free nucleus are created to uniformly distribute into the melt to greatly refine and homogeneousize the water-quenched microstructure at near liquidus temperature (1 508 ℃), and it do so at air-cooled conditions. Electromagnetic stirring in medium-frequency induction furnace can greatly increase nucleus amounts at near liquidus temperature with short holding time and then keep the morphology and amounts of the nucleus. So change of the water-quenched microstructure of the semi-solid slurries can not be observed at holding for 5~50 min.

关 键 词：半固态 近液相线 低合金钢 组织 

分 类 号：TG249.9[金属学及工艺—铸造]