论文部分内容阅读
本厂承接各类熔模铸钢件品种多达千种,其中一些形状复杂的零件,特别是框形件和长形件极易产生裂纹,经分析观察均为热裂,多数部位出现于内浇口的对面和附近的四角处,以及铸件未加补缩的小热节处。经采取各种防除措施基本上得到了解决。现根据多年实践谈一些粗浅看法。 热裂产生的温度范围约在合金的固相线附近,当铸件结构复杂或由于浇注系统的影响。铸件局部会出现滞后冷却凝固的现象,当铸件其它部分已经凝固并产生收缩时,这一部分金属仍处于半凝固状态,其强度接近于
The factory to undertake all kinds of investment casting steel up to thousands of species, some of the complex shape of the parts, especially the frame-shaped pieces and pieces of long-easy to crack, the analysis were observed hot cracking, most parts appear in the Opposite the gate and near the four corners, as well as the castings of small hot joints. After taking a variety of control measures have basically been resolved. Now based on years of practice to talk about some superficial views. Thermal cracking produces temperatures in the vicinity of the solidus of the alloy when the structure of the casting is complex or due to the influence of the casting system. Casting parts will appear after the cooling and solidification of the phenomenon of lagging, when the rest of the casting has been solidified and contraction occurs, this part of the metal is still in a semi-solidified state, its strength close to