Transactions of Materials and Heat Treatment

Title：Analysis on unqualified reasons for mechanical properties of wind power flange of 42CrMoA

Authors： Gao Dongsheng Li Yafeng Li Fusheng Kang Xiying Guo Hongfei

Unit： National Flange Forging Products Quality Supervision and Inspection Center (Shanxi) Xinzhou Institute of Quality Inspection and Technical Testing

KeyWords： wind power flange steel 42CrMoA mechanical properties failure analysis inclusion

ClassificationCode：TG142.1

year,vol(issue):pagenumber：2018,43(4):159-162

Abstract：

For the wind power flange of steel 42CrMoA, the unqualified reasons of its mechanical properties were analyzed by chemical composition analysis, gas content analysis, stretching test, Charpy impact test, metallographic examination and SEM-EDS analysis. The results show that the chemical composition and gas content of steel 42CrMoA meet the standard requirements, and the tensile strength (Rm=693 MPa) and the lower yield strength (ReL=463 MPa) are lower than the standard required Rm (800-950 MPa) and ReL (more than 550 MPa) respectively. Then, two values of the Charpy impact test at -40 ℃ are not qualified, meanwhile one value is qualified, furthermore the average value is less than 27 J. Considering the results of metallographic examination and SEM-EDS analysis, it is concluded that the insufficient heating temperature of material in the quenching and tempering treatment leads to the appearance of long strip ferrite in the steel, and the uniform chemical composition of material leads to a great difference in the Charpy absorbed energy in different parts. In addition, the large inclusions over 100 μm are found at the impact fracture, which causes further damage to the properties of steel.

Funds：

高东升（1966-），男，工学学士，高级工程师；E-mail：gds6763@163.com；通讯作者：李亚峰（1990-），男，硕士，助理工程师；E-mail：170226547@qq.com

Reference：

[1]李杰,王国梁,夏云进,等.铌钒微合金化对风电法兰用Q345E钢析出相的影响[J].材料导报,2014, 28 (14): 104-108.

Li J, Wang G L, Xia Y J, et al. Effect of Nb and V micro-alloying on the precipitation phases in Q345E for wind-electron flange [J]. Materials Review, 2014, 28 (14): 104-108.

[2]王光艳,梅益,陈浪, 等.42CrMo环件轧制成形的数值模拟与分析[J].锻压技术,2014,39(5):82-86.

Wang G Y, Mei Y, Chen L, et al. Numerical simulation and analysis of rolling forming of 42CrMo rings [J]. Forging ＆ Stamping Technology, 2014,39(5):82-86.

[3]何云龙,范鼎东,孙维, 等.高韧性风电法兰用钢的冶炼工艺研究与实践[J].炼钢,2014,30(2):14-17.

He Y L, Fan D D, Sun W, et al. Study and practice on smelting process of high toughness wind power flange steel [J]. Steelmaking, 2014,30(2):14-17.

[4]戈文英.风电塔筒法兰用S355NL钢的低温冲击韧性[J].特殊钢,2015,36(5):47-50.

Ge W Y. Low temperature impact toughness of steel S355NL for wind power tower flange [J]. Special Steel, 2015,36(5):47-50.

[5]NB/T 31025—2012，风力发电机组环形锻件标准[S].

NB/T 31025—2012，Ring type forgings of wind turbine generator system[S].

[6]Bashu S A, Singh K, Rawat M S. Effect of heat treatment on mechanical properties and fracture behaviour of a 12CrMoV steel[J]. Materials Science & Engineering A，1990，127 (1)：7-15.

[7]Wang P, Lu S P, Xiao N M, et al. Effect of delta ferrite on impact properties of low carbon 13Cr-4Ni martensitic stainless steel[J]. Materials Science and Engineering A, 2010, 527 (13): 3210-3216.

[8]陈俊丹,莫文林,王培,等.回火温度对42CrMo钢冲击韧性的影响[J].金属学报,2012,48(10):1186-1193.

Chen J D, Mo W L, Wang P, et al. Effects of tempering temperature on the impact toughness of steel 42CrMo[J]. Acta Metallugica Sinica, 2012,48(10):1186-1193.

[9]Zhang L F, Thomas B G. State of the art in evaluation and control of steel cleanliness [J]. ISIJ International, 2003,43 (3):271-291.

Service：

【This site has not yet opened Download Service】【Add Favorite】