Nanobainite Generated in Low‐ and Medium‐Carbon Steels via an Economical Alloying Strategy
Nanobainite Generated in Low‐ and Medium‐Carbon Steels via an Economical Alloying Strategy
复制标题
通过经济的合金化策略在低碳钢和中碳钢中生成纳米贝氏体
DOI：
10.1002/srin.202100575
复制
发表时间：
2021
影响因子：
2.2
通讯作者：
Mohamed
中科院分区：
文献类型：
--
作者：
Mohamad;Palkowski;Soliman;Mohamed
A low‐cost strategy for generating fast transforming nanobainitic (nB) steels in low‐ and medium‐carbon alloys is investigated. Accelerating the bainite transformation relies on adding 0.7–3 wt% Al. Alloys and heat treatments are designed via thermodynamic calculations and dilatometry. nB microstructures are generated via isothermal holding and continuous cooling. The microstructures generated are investigated via microscopy and mechanical characterization. Incubation periods less than 150 s as well as isothermal transformation times ranging from 2000 to 4000 s are recorded for all conditions. Increasing the Al content from 0.7 to 2.8 wt% lowers the incubation and transformation times from 150 to 15 s and 3000 to 2000 s, respectively, at a cost of a reduction in tensile strength and elongation % (EL%) from 1330 to 1270 MPa and from 13.5 to 7.7%, respectively. The introduction ofδ‐ferrite to the microstructure of the high Al alloy increased EL% up to 16% and reduced the tensile strength to 1105 MPa. Continuous cooling at a rate of 0.03 K s−1increased the tensile strength by 100 MPa at similar EL%. Lowering the cooling rate to 0.003 K s−1yielded similar properties as isothermal treatment because most of the transformation is concluded near the starting temperature.
