Scholarlink

<p>The effect of initial carbon heterogeneity on isothermal oxidation and decarburization behaviors of a commercial spring steel, 60Si2CrV, at 900&#xa0;°C has been investigated using three initial microstructures, named lamellar martensite (LM), lamellar pearlite (LP), and spheroidal pearlite (SP). Owing to the coupled effects of distinct austenitization reversion and decarburization-induced carbon gradient near the surface, the prior austenite grain size in the subsurface region follows the order LM &lt; LP &lt; SP. The LM specimen exhibits the highest oxidation and decarburization rates, attributable to its smallest subsurface austenite grains which provide a higher density of grain boundary diffusion pathways. In contrast, the SP specimen shows the lowest oxidation and decarburization rates because of its largest subsurface austenite grain size and the retardation effects by Cr and Mn enriched carbides. During isothermal holding at 900&#xa0;°C, decarburization ferrite thickness–time curves feature an inflection point at around 240&#xa0;minutes, marking a transition to a faster decarburization kinetic regime for holding times beyond this threshold. Kinetic simulations of the decarburization process indicate that this behavior may be associated with subsurface austenite grain growth, which alters the effective carbon diffusivity (<InlineEquation ID="IEq1"> <EquationSource Format="TEX">\({D}_{\text{eff}}\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>D</mi> <mtext>eff</mtext> </msub> </math></EquationSource> </InlineEquation>) in austenite.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Influence of Initial Carbon Heterogeneity on Surface Decarburization and Oxidation Kinetics of 60Si2CrV Spring Steel

  • 期刊论文

  • 发表日期：

    2026年4月12日

查看全文
  • Jintong Chen,
  • Danfeng Xu,
  • Naiyou Xiao,
  • Borui Zhang,
  • Tao Jia

摘要

The effect of initial carbon heterogeneity on isothermal oxidation and decarburization behaviors of a commercial spring steel, 60Si2CrV, at 900 °C has been investigated using three initial microstructures, named lamellar martensite (LM), lamellar pearlite (LP), and spheroidal pearlite (SP). Owing to the coupled effects of distinct austenitization reversion and decarburization-induced carbon gradient near the surface, the prior austenite grain size in the subsurface region follows the order LM < LP < SP. The LM specimen exhibits the highest oxidation and decarburization rates, attributable to its smallest subsurface austenite grains which provide a higher density of grain boundary diffusion pathways. In contrast, the SP specimen shows the lowest oxidation and decarburization rates because of its largest subsurface austenite grain size and the retardation effects by Cr and Mn enriched carbides. During isothermal holding at 900 °C, decarburization ferrite thickness–time curves feature an inflection point at around 240 minutes, marking a transition to a faster decarburization kinetic regime for holding times beyond this threshold. Kinetic simulations of the decarburization process indicate that this behavior may be associated with subsurface austenite grain growth, which alters the effective carbon diffusivity ( \({D}_{\text{eff}}\) D eff ) in austenite.