第36卷增刊1 北京科技大学学报 Vol.36 Suppl.1 2014年4月 Journal of University of Science and Technology Beijing Apr.2014 Zr对Fe-36Ni因瓦合金凝固组织和热塑性的影响 郑宏光，李元”，刘旭峰” 1)宝钢研究院炼钢研究所，上海2019002)宝钢特钢有限公司，上海200940 ☒通信作者，E-mail:zhenghongguang@baosteel.com 摘要研究了Z对Fe-36Ni因瓦合金组织和热塑性的影响及相关作用机制.结果表明：加入质量分数为0.081%Z:处理 后，合金中形成了大量高熔点的Z0,颗粒：错配度计算表明，Z0,(001)面与合金基体的(001)面之间的错配度仅为0.77%， 因此，Z0,可以作为有效的非均质形核核心，使柱状晶变短变细，等轴晶比例增加，凝固组织得到显著改善.温度低于1050℃ 时，F-36Ni因瓦合金热塑性较差，晶界强度较低及晶界滑移是其主要断裂机制：Zr通过细化品粒来强化晶界、限制晶界的滑 移和促进晶界的迁移，从而显著提高了合金950~1000℃的热塑性：温度高于1050℃，由于动态再结晶的出现，合金展现出了 良好的热塑性 关键词Fe-36Ni因瓦合金：Zr;凝固组织：热塑性 分类号T℉775 Effects of Zr on the solidification structure and hot ductility of Fe-36Ni invar alloy ZHENG Hong-guang,LI Yuan?,LIU Xu-feng) 1)Steelmaking Dept,R&D Center,Baosteel,Shanghai 201900,China 2)Baosteel Special Materials Steel Co.Ltd,Shanghai 200940,China Corresponding author,E-mail:zhenghongguang@baosteel.com ABSTRACT Effects of Zr on the solidification structure and hot ductility of Fe36Ni invar alloy were investigated,and the corre- sponding mechanisms were also discussed.Results showed that a great amount of high-melting point compounds (Zr0)formed in the alloy with the addition of 0.081%Zr (mass fraction).Based on the theory of lattice misfit,the lattice misfit between (001)surfaces of ZrO and the Fe-36Ni matrix is 0.77%,which is relatively low.Therefore,ZrO,could serve as the effective core of heterogeneous nucleation,resulting in remarkably shorter and thinner columnar grains,which increases the proportion of equiaxed grains and refines the solidification structure.The alloy has a bad hot ductility below 1050C,which is mainly attributed to weaker boundaries and grain boundary sliding.However,the hot ductility of the alloy is highly enhanced at 950-1000C because of the addition of 0.081%Zr, which could refine grain sizes to hinder grain boundary sliding,strengthen grain boundaries,and promote grain boundary movement. The alloy has a good hot ductility over 1050C for the existing of dynamic recrystallization. KEY WORDS Fe-36Ni invar alloy:Zr:solidification structure:hot ductility Fe-36Ni因瓦合金具有极低的热膨胀系数，用 期连铸板坯热轧时出现开裂现象.分析认为，其连 途广泛.其产品应用已从传统精密仪器行业向电子 铸板坯凝固组织主要由粗大柱状晶组成，这可能对 工业和特殊结构材料行业拓展，需求量不断扩 热轧开裂有较大影响.据文献报道，粗大的柱状晶 大-).该合金传统生产工艺主要采用模铸、电渣重 会加剧连铸坯的裂纹敏感性，恶化其热塑性4.晶 熔等，但传统工艺生产效率低下，成本较高.采用立 粒细化在一定程度上可改善某些合金热塑性.添加 式板坯连铸工艺可大幅度提高生产效率，但生产初 Ti,Ca,Zr和Y等微合金化元素具有改善某些合金 收稿日期：2013-11-21 DOI:10.13374/j.issn1001-053x.2014.s1.027:http://jourals.ustb.edu.en第 36 卷 增刊 1 2014 年 4 月 北京科技大学学报 Journal of University of Science and Technology Beijing Vol． 36 Suppl． 1 Apr． 2014 Zr 对 Fe--36Ni 因瓦合金凝固组织和热塑性的影响 郑宏光1) ，李 元2) ，刘旭峰1) 1) 宝钢研究院炼钢研究所，上海 201900 2) 宝钢特钢有限公司，上海 200940  通信作者，E-mail: zhenghongguang@ baosteel． com 摘 要 研究了 Zr 对 Fe--36Ni 因瓦合金组织和热塑性的影响及相关作用机制． 结果表明: 加入质量分数为 0. 081% Zr 处理 后，合金中形成了大量高熔点的 ZrO2颗粒; 错配度计算表明，ZrO2 ( 001) 面与合金基体的( 001) 面之间的错配度仅为 0. 77% ， 因此，ZrO2可以作为有效的非均质形核核心，使柱状晶变短变细，等轴晶比例增加，凝固组织得到显著改善． 温度低于 1050 ℃ 时，Fe--36Ni 因瓦合金热塑性较差，晶界强度较低及晶界滑移是其主要断裂机制; Zr 通过细化晶粒来强化晶界、限制晶界的滑 移和促进晶界的迁移，从而显著提高了合金 950 ～ 1000 ℃的热塑性; 温度高于 1050 ℃，由于动态再结晶的出现，合金展现出了 良好的热塑性． 关键词 Fe--36Ni 因瓦合金; Zr; 凝固组织; 热塑性 分类号 TF775 Effects of Zr on the solidification structure and hot ductility of Fe-36Ni invar alloy ZHENG Hong-guang1)  ，LI Yuan2) ，LIU Xu-feng1) 1) Steelmaking Dept，Ｒ＆D Center，Baosteel，Shanghai 201900，China 2) Baosteel Special Materials Steel Co． Ltd，Shanghai 200940，China  Corresponding author，E-mail: zhenghongguang@ baosteel． com ABSTＲACT Effects of Zr on the solidification structure and hot ductility of Fe-36Ni invar alloy were investigated，and the corre￾sponding mechanisms were also discussed． Ｒesults showed that a great amount of high-melting point compounds ( ZrO2 ) formed in the alloy with the addition of 0. 081% Zr ( mass fraction) ． Based on the theory of lattice misfit，the lattice misfit between ( 001) surfaces of ZrO2 and the Fe-36Ni matrix is 0. 77% ，which is relatively low． Therefore，ZrO2 could serve as the effective core of heterogeneous nucleation，resulting in remarkably shorter and thinner columnar grains，which increases the proportion of equiaxed grains and refines the solidification structure． The alloy has a bad hot ductility below 1050 ℃，which is mainly attributed to weaker boundaries and grain boundary sliding． However，the hot ductility of the alloy is highly enhanced at 950 ～ 1000 ℃ because of the addition of 0. 081% Zr， which could refine grain sizes to hinder grain boundary sliding，strengthen grain boundaries，and promote grain boundary movement． The alloy has a good hot ductility over 1050 ℃ for the existing of dynamic recrystallization． KEY WOＲDS Fe-36Ni invar alloy; Zr; solidification structure; hot ductility 收稿日期: 2013--11--21 DOI: 10． 13374 /j． issn1001--053x． 2014． s1． 027; http: / /journals． ustb． edu． cn Fe--36Ni 因瓦合金具有极低的热膨胀系数，用 途广泛． 其产品应用已从传统精密仪器行业向电子 工业和特殊结构材料行业拓展，需 求 量 不 断 扩 大［1--3］． 该合金传统生产工艺主要采用模铸、电渣重 熔等，但传统工艺生产效率低下，成本较高． 采用立 式板坯连铸工艺可大幅度提高生产效率，但生产初 期连铸板坯热轧时出现开裂现象． 分析认为，其连 铸板坯凝固组织主要由粗大柱状晶组成，这可能对 热轧开裂有较大影响． 据文献报道，粗大的柱状晶 会加剧连铸坯的裂纹敏感性，恶化其热塑性［4--6］． 晶 粒细化在一定程度上可改善某些合金热塑性． 添加 Ti，Ca，Zr 和 Y 等微合金化元素具有改善某些合金