铸钢件冒口离开热节凝固时间的试验研究

A Study on Solidification Time of Steel Casting With Riser Away from Hot Spot

测温试验表明，冒口放在热节上，热节处的凝固时间延长８０％；冒口离开热节的距离为１．６８倍热节圆直径时，冒口对热节的热影响基本消失。冒口离开热节放在次热节或薄壁处，形成的接触热节可使该处凝固时间延长４０．４％。

The temperature measuring results show that in case that the riser is located on hot spot, the solidifications time of hot spot is prolonged by 80%. The thermal influence of riser on hot spot disppeared when the distance between the centre of riser and geometry centre of hot spot is 1.68 times of the hot spot diameter. Upon conditions that the riser is away from hot spot and located on secondary hot spot or thin wall, the local solidification time is delayed 40.4% . As a result of local neighbourhood, it is advantageous to establishing the dynamic directional solidification from thin wall to hot spot, and to neighbourhood, towards riser.