Transactions of Materials and Heat Treatment

Title：Optimization on forging process of square valve body for F55 duplex stainless steel

Authors：

Unit：

KeyWords： duplex stainless steel valve body α phase γ phase deformation zone

ClassificationCode：TG316.2

year,vol(issue):pagenumber：2021,46(6):54-57

Abstract：

The forging process was improved by analyzing the solid solution and precipitation mechanism of nitrogen in F55 duplex stainless steel in the forging temperature range to solve the problems of surface cracks of the blank after forging and delayed surface cracking after processing of large-size F55 duplex stainless steel, and the nitrogen precipitated along the grain boundary was difficult to dissolve in the structure again resulting in a large internal stress. Then, during the forging deformation process, the tensile stress promoted the precipitation of nitrogen in the structure, and the compressive stress prevented and promoted the diffusion of precipitated nitrogen into the structure. Therefore, the internal stress state of blank should be controlled during the forging process to make it in a compressive stress state, and the excessive non-deformation zone and micro-deformation zone inside the blank were avoided. In addition, the use of “V”-shaped anvil was an effective method when forging. At the same time, the method of the first small deformation and then large deformation changed the internal deformation stress state and effectively avoided the large tensile stress formed inside when the circular section was forged into a square shape. Finally, when the included angle of “V”-shaped anvil was 135°, the internal compressive stress state of blank was the best.

Funds：

工信部船用低速柴油机原理样机研制资助（CDGC01-KT0103）

孙常奋（1965-），男，硕士，高级工程师 E-mail：dt_SUN@126.com

Reference：

[1]王明家，马千，李景丽，等.热老化对核级316LN锻造控氮奥氏体不锈钢微观组织及性能的影响[J].燕山大学学报，2013,(5):385-388，401.

Wang M J, Ma Q, Li J L, et al．Influence of thermal aging on microstructure and mechanical properties of nuclear grade 316LN forged austenitic stainless steel[J]. Journal of Yanshan University, 2013,(5):385-388，401.

[2]闫志波，赵海涛，陈红卫. 301不锈钢螺栓断裂原因分析 [J]. 锻压技术，2020,45(10):7-12.

Yan Z B,Zhao H T,Chen H W. Cause analysis of fracture for 301 stainless steel bolt [J]. Forging & Stamping Technology，2020,45(10):7-12.

[3]杨胜龙，顾立东.超级双相不锈钢锻件F53和F55的质量控制要素[J].冶金管理，2019,(9):45-46.

Yang S L, Gu L D. The quality controlling elements of F53 and F55 super stainless steel forgings[J]. Steel Management, 2019, (9):45-46.

[4]黄嘉琥.压力容器用含氮不锈钢[J].压力容器，2013,30(10):42-53,71.

Huang J H. Nitrogen-bearing stainless steels for pressure vessel [J]. Pressure Vessel Technology, 2013, 30(10):42-53,71.

[5]宋红梅，丁秀平，刘雄，等.高温时效2205双向不锈钢中的组织转变[J].材料热处理学报，2010,31(3):43-47.

Song H M, Ding X P, Liu X, et al. Microstructure evolution in a 2205 duplex stainless steel during aging at high temperature [J]. Transactions of Materials and Heat Treatment, 2010,31(3):43-47.

[6]于海成，严与辉，刘小杨，等.双向不锈钢成分、性能及析出相分析[J].特殊钢，2019,40(6):53-58.

Yu H C, Yan Y H, Liu X Y, et al. Analysis on composition,properties, and precipitated phases of duplex stainless steel [J]. Special Steel, 2019,40(6):53-58.

[7]庄飚.0Cr21Ni14Mn5Mo2N不锈钢闪光焊裂纹原因分析[J].材料开发与应用，2018,33(6):12-15.

Zhuang B. Analysis on crack of flash butt weldment of 0Cr21Ni14Mn5Mo2N stainless steel [J]. Development and Application of Materials, 2018, 33(6):12-15.

[8]谢春乾，王刚，韩赟，等.汽车用780 MPa级别双相钢氢致延迟开裂行为的研究[J].热加工工艺，2018,(22):74-77.

Xie C Q, Wang G, Han B, et al. Research on hydrogen induced delayed cracking behavior of 780 MPa grade dual phase steel for automotive[J]. Hot Working Technology, 2018,(22):74-77.

[9]王振华.高氮铬锰奥氏体钢的热变形行为及热锻开裂机理研究[J].材料导报，2012,(12):5.

Wang Z H. Study on hot deforming behavior and cracking mechanisms during hot forging of high nitrogen CrMn austenic steel [J]. Materials Review, 2012,(12):5.

[10]宁小智，邢长军，雍岐龙.热拔工艺对高氮无镍奥氏体不锈钢线材开裂的影响[J].中国冶金，2020,30(5):47-50,75.

Ning X Z, Xing C J, Yong Q L. Influence of hot drawing process on cracking of high nitrogen nickel free austenitic stainless steel wire rod [J]. China Metallurgy, 2020,30(5):47-50,75.

[11]姚可夫，唐廼泳，陈南平.双向不锈钢中裂纹尖端塑性变形行为的透射电镜原位观察[J].金属学报，1989,25(6):213-218.

Yao K F, Tang N Y, Chen N P. In-situ observation of crack tip deformation in a duplex stainless steel [J]. Acta Metallurgica Sinica, 1989,25(6):213-218.

[12]王以华，吴振清，陈修琳，等.型砧几何尺寸对大锻件锻造孔隙闭合的影响[J].金属加工:热加工，2013, (1):22-25.

Wang Y H, Wu Z Q, Chen X L, et al. Influence of the type anvil size on gap closing of the large forging during processing [J]. Metal Working, 2013, (1):22-25.

[13]孙常奋，胡金华，吴鹏，等.大型船用柴油机连杆晶粒细化锻造工艺[J].锻压技术，2020，45(5): 34-37.

Sun C F, Hu J H, Wu P, et al. Grain refining forging technology of connecting rod of large marine diesel engine[J].Forging & Stamping Technology, 2020,45(5): 34-37.

Service：

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