硅含量对耐热球墨铸铁显微组织和力学性能的影响

doi:10.13251/j.issn.0254-6051.2022.09.039

摘要/Abstract

摘要： 采用光学显微镜、扫描电镜、电子万能拉伸试验机测试分析手段,研究硅含量对耐热球墨铸铁显微组织和室温、高温力学性能的影响规律。试验结果表明,随着硅含量的增加,石墨圆整度逐渐下降,硅含量(质量分数,下同)达到3.8%时,基体中开始出现碎块状石墨,球化级别为3级。随着硅含量从2.8%增加至4.8%,珠光体含量从51.06%减少至8.65%。随着硅含量的增加,室温抗拉强度先上升后下降,伸长率逐渐下降,当硅含量为3.8%时,抗拉强度为726 MPa,伸长率为1.6%。随着硅含量的增加,高温抗拉强度逐渐上升,伸长率逐渐下降,当硅含量为4.8%时,抗拉强度为532 MPa,伸长率为6%。室温拉伸断口出现大量的解理面和河流花样,表现形式为脆性断裂。高温拉伸断口出现韧窝和撕裂棱,拉伸断口表现形式为韧-脆混合型断裂。

关键词: 耐热球墨铸铁, 显微组织, 室温性能, 高温性能, 断口形貌

Abstract: The influence of silicon content on microstructure and mechanical properties of heat-resistant nodular cast iron at room temperature and high temperature was studied by means of optical microscope, scanning electron microscope and electronic universal tensile testing machine. The test results show that with the increase of silicon content, the roundness of graphite gradually decreases. When the silicon content(mass fraction, similarly hereinafter) reaches 3.8%, fragmented graphite begins to appear in the matrix, and the spheroidization grade is grade 3. As the silicon content increases from 2.8% to 4.8%, the pearlite content decreases from 51.06% to 8.65%. With the increase of silicon content, the room temperature tensile strength first increases and then decreases, and the elongation decreases gradually. When the silicon content is 3.8%, the tensile strength is 726 MPa and the elongation is 1.6%. With the increase of silicon content, the high temperature tensile strength gradually increases and the elongation decreases gradually. When the silicon content is 4.8%, the tensile strength is 532 MPa and the elongation is 6%. A large number of cleavage planes and river patterns appear in the tensile fracture at room temperature, and the form is brittle fracture. Dimples and tear edges appear in the high temperature tensile fracture, and the tensile fracture form is ductile-brittle mixed fracture.

Key words: heat-resistant nodular cast iron, microstructure, room-temperature properties, high-temperature properties, fracture morphology

中图分类号:

TG143.5

赵竞, 王丽萍, 冯义成, 姜文勇, 王雷, 郭二军. 硅含量对耐热球墨铸铁显微组织和力学性能的影响[J]. 金属热处理, 2022, 47(9): 227-233.

Zhao Jing, Wang Liping, Feng Yicheng, Jiang Wenyong, Wang Lei, Guo Erjun. Effect of silicon content on microstructure and mechanical properties of heat-resistant nodular cast iron[J]. Heat Treatment of Metals, 2022, 47(9): 227-233.

参考文献

[1]张慧芳, 吕栋, 张泉, 等. QT400球墨铸铁的热疲劳行为[J]. 金属热处理, 2016, 44(11): 71-75.
Zhang Huifang, Lü Dong, Zhang Quan, et al. Thermal fatigue behavior of ductile iron QT400[J]. Heat Treatment of Metals, 2016, 44(11): 71-75.
[2]那顺桑, 何惠岚, 田波, 等. 热疲劳作用下球墨铸铁组织变化规律[J]. 金属热处理, 2013, 38(6): 43-46.
Na Shunsang, He Huilan, Tian Bo, et al. Microstructure change of nodular cast iron under thermal fatigue[J]. Heat Treatment of Metals, 2013, 38(6): 43-46.
[3]周珊, 孙有平, 付静, 等. 球墨铸铁QT800-6的热压缩变形行为及应变补偿本构模型[J]. 金属热处理, 2018, 43(7): 49-53.
Zhou Shan, Sun Youping, Fu Jing, et al. Hot compression deformation behavior and strain compensated constitutive model of QT800-6 ductile iron[J]. Heat Treatment of Metals, 2018, 43(7): 49-53.
[4]邓丽霞, 高生祥. 铜微合金化对QT600球墨铸铁组织和性能的影响[J]. 金属热处理, 2016, 41(4): 38-41.
Deng lixia, Gao Shengxiang. Effect of Cu microalloying on microstructure and properties of QT600 nodular cast iron[J]. Heat Treatment of Metals, 2016, 41(4): 38-41.
[5]陈光辉, 王振, 郝长利. 重载车曲轴用球磨铸铁的合金化与热处理[J]. 金属热处理, 2019, 44(1): 102-107.
Chen Guanghui, Wang Zhen, Hao Changli. Alloying and heat treatment of ductile cast iron for heavy duty vehicle crankshaft[J]. Heat Treatment of Metals, 2019, 44(1): 102-107.
[6]袁献文. 国内耐热铸铁的发展和应用[J]. 铸造技术, 1984(3): 49-54.
Yuan Xianwen. Development and application of heat resistant cast iron in China[J]. Foundry Technology, 1984(3): 49-54.
[7]古可成, 刘红. 国内耐热铸铁的进展[J]. 铸造, 1998(3): 51-54.
Gu Kecheng, Liu Hong. Development of heat resistant cast iron in china[J]. Foundry, 1998(3): 51-54.
[8]高峰, 郭为忠, 宋清玉, 等. 重型制造装备国内外研究与发展[J]. 机械工程学报, 2010, 46(19): 92-107.
Gao Feng, Guo Weizhong, Song Qingyu, et al. Current development of heavy-duty manufacturing equipments[J]. Journal of Mechanical Engineering, 2010, 46(19): 92-107.
[9]李蒙. 低镁球化剂和球化处理温度对球铁组织性能的影响[J]. 材料热处理学报, 2016, 37(5): 121-127.
Li Meng. Influences of low-Mg-nodulizer and spheroidizing temperature on microstructure and mechanical property of ductile cast iron[J]. Transactions of Materials and Heat Treatment, 2016, 37(5): 121-127.
[10]彭建中, 刘玲霞, 杨忠贤. 大型风电球墨铸铁轮毂的质量控制[J]. 铸造, 2010, 59(9): 969-972, 976.
Peng Jianzhong, Liu Lingxia, Yang Zhongxian. Quality control measures for heavy ductile iron hub of wind turbine generator[J]. Foundry, 2010, 59(9): 969-972, 976.
[11]李蒙. 多元合金化大断面球墨铸铁组织和性能的分析[J]. 中国冶金, 2019, 29(4): 47-53, 74.
Li Meng. Analysis onmicrostructure and properties of multi-alloyed heavy section ductile iron[J]. China Metallurgy, 2019, 29(4): 47-53, 74.
[12]马敬仲, 曾艺成. 厚大断面球墨铸铁件生产中若干问题的探讨(1)[J]. 现代铸铁, 2020, 40(1): 1-5.
Ma Jingzhong, Zeng Yicheng. A discussion on some problems in heavy section nodular iron production (I)[J]. Modern Cast Iron, 2020, 40(1): 1-5.
[13]宁保群, 严泽生, 付继成, 等. T91铁素体耐热钢强化新途径[J]. 材料导报, 2009, 23(7): 72-76.
Ning Baoqun, Yan Zesheng, Fu Jicheng, et al. New strengthening methods of T91 ferritic heat resistant steel[J]. Materials Reports, 2009, 23(7): 72-76.
[14]龙琼, 伍玉娇, 凌敏, 等. 稀土元素处理钢的研究进展及应用前景[J]. 炼钢, 2018, 34(1): 57-64, 70.
Long Qiong, Ww Yujiao, Ling Min, et al. Research and prospect on rare earth treated steel[J]. Steelmaking, 2018, 34(1): 57-64, 70.
[15]高乾. 耐热球铁模具材料开发[D]. 长春: 吉林大学, 2009.
Gao Qian. Development of heat-resistant ductile iron for die materials[D]. Changchun: Jilin University, 2009.
[16]吴晓明, 徐锦锋, 韩非, 等. Cr、V元素对高硅钼球铁热疲劳性能的影响[J]. 铸造, 2020, 69(11): 1131-1138.
Wu Xiaoming, Xu Jinfeng, Han Fei, et al. Effects of vanadium and chromium elements on thermal fatigue properties of high Si-Mo ductile iron[J]. Foundry, 2020, 69(11): 1131-1138.
[17]许帅领. 铝和铬对耐热球墨铸铁组织及性能的影响[D]. 郑州: 郑州大学, 2019.
Xu Shuailing. The influence of aluminum and chromium on the structure and properties of heat-resistant ductile iron[D]. Zhengzhou: Zhengzhou University, 2019.
[18]刘丹, 袁峰, 陈慧, 等. 发动机排气歧管失效分析[J]. 热处理, 2012, 27(6): 61-65.
Liu Dan, Yuan Feng, Chen Hui, et al. Failure analysis on auto engine exhaust manifold[J]. Heat Treatment, 2012, 27(6): 61-65.
[19]Richard L, 申泽骥. 固溶强化铁素体球墨铸铁[J]. 铸造, 2010, 59(6): 622-627.
Richard L, Shen Zeji. Solution strengthened ferritic ductile iron[J]. Foundry, 2010, 59(6): 622-627.
[20]古可成, 顾玉娜, 李义尧, 等. 硅系耐热球铁的脆性研究[J]. 钢铁, 2001, 36(1): 56-59.
Gu Kecheng, Gu Yuna, Li Yiyao, et al. Research of brittleness of silicon bearing heat-resisting ductile iron[J]. Iron and Steel, 2001, 36(1): 56-59.
[21]王志强. Nb、Sb对球墨铸铁组织及力学性能的影响研究[D]. 长春: 吉林大学, 2020.
Wang Zhiqiang. Effect of Nb and Sb on microstructure and mechanical properties of ductile iron[D]. Changchun: Jilin University, 2020.
[22]吴连生. 断口分析及其应用之二[J]. 理化检验. 物理分册, 1978(2): 35-43, 49.
[23]周惦武, 彭平, 赖海萍, 等. QT400-18铸态高韧性球墨铸铁拉伸断口特征与断裂机理[J]. 铸造, 2004, 53(6): 443-446.
Zhou Dianwu, Peng Ping, Lai Haiping, et al. Fracture character and fracture mechanism of the tensile sample of QT400-18 as-cast high toughness ductile iron[J]. Foundry, 2004, 53(6): 443-446.