(1. 北京科技大学 材料先进制备技术教育部重点实验室，北京 100083；
2. 北京科技大学 现代交通金属材料与加工技术北京实验室，北京 100083；
3. 中南大学 材料科学与工程学院，长沙 410083；
4. 宁夏东方有色金属集团公司，石嘴山 75300)
摘 要: 采用热冷组合铸型(HCCM)水平连铸工艺制备了宽度300 mm、厚度10 mm的Cu-0.36%Be-0.46%Co(质量分数)合金板材，研究制备参数对连铸合金板材固/液界面位置和形状、表面质量和组织的影响规律。结果表明：随着热型加热温度的降低、冷型段一次冷却水流量的增大和拉坯速度的降低，合金板材的表面质量随之提高。随着热型加热温度的升高、一次冷却水流量的减小和拉坯速度的增大，合金固/液界面位置从热型段向冷型段移动，沿板材宽度方向的固/液界面形状由凸向固相的“U”状转变为“W”状，且凸向固相程度增大，组织变化为粗大平直柱状晶→细长对称倾斜柱状晶→混晶→等轴晶。合理的制备参数为热型加热温度1100 ℃、拉坯速度50 mm/min、一次冷却水流量Qul=Qur=400 h/L、Qum=600 h/L、Qll=Qlr=400 h/L和Qlm=600 h/L。所制备的合金板材具有良好的表面质量和沿连铸方向柱状晶组织，表面粗糙度Ra=2.2 μm，屈服强度和抗拉强度分别为212 MPa和353 MPa，断后伸长率为35.0%，无需表面处理可直接用于后续冷轧加工。
关键字: 铍铜板材；HCCM水平连铸；表面质量；组织；力学性能
（1. Key Laboratory for Advanced Materials Processing, Ministry of Education, University of Science and Technology Beijing, Beijing 100083, China;
2. Beijing Laboratory of Metallic Materials and Processing for Modern Transportation, University of Science and Technology Beijing, Beijing 100083, China;
3. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
4. China Nonferrous Metal Mining (Group), Ningxia Orient Group Co., Ltd., Shizuishan 753000, China）
Abstract:Cu-0.36%Be-0.46%Co (mass fraction) plate with width of 300 mm and thickness of 10 mm was produced by HCCM horizontal continuous casting, the influences of preparing parameters on the solid-liquid interface position and shape, surface quality and microstructure of alloy were studied. The results show that with the decreases of mold heating temperature and casting speed as well as the increase of cooling water flow rate, the surface quality of the alloy improves. With the increases of mold heating temperature and casting speed as well as the decrease of cooling water flow rate, the position of the solid-liquid interface moves from the hot mold to the cool mold, the shape of solid-liquid interface along the width of plate changes from the U-shape convex to solid phase to W-shape. With the increase of the convexity degree to solid phase, the microstructure evolves as coarsen and straight columnar grains→slender symmetrically inclined columnar grains→mixed grains→equiaxed grains. The reasonable preparing parameters are the mold heating temperature 1100 ℃, the casting speed 50 mm/min and cooling water flow rate 400-600-400 L/h. The prepared alloy plate has good surface quality and columnar grains along casting direction, with surface ronghness of Ra=2.2 μm, yield strength of 212 MPa, tensile strength of 353 MPa and elongation to failure of 35.0%, which can be directly used for cold rolling without surface treatment.
Key words: beryllium copper plate; HCCM horizontal continuous casting; surface quality; microstructure; mechanical properties
