![]() Shao: Study on the Precipitation Behavior and Micronization of MnS Inclusion in Steel, University of Science and Technology Beijing, Beijing, 2011. It is the existence of the interstitial phase that can make densification happen normally, and then make MnS particles reach equilibrium state. Manganese is a very common alloy element in steels produced by ingot metallurgy (IM) in fact so common that steel grades containing up to 0.4 of Mn are still regarded as ‘unalloyed’ Citation 1. The effective sintering stress F S increases with the equilibrium angle Ψ, and the sintering force becomes zero when the equilibrium configuration is reached. At the later stage of holding and cooling at 1443 K (1170 ☌), the sintering of MnS is promoted by the coupling of grain boundary diffusion and surface diffusion. The grain boundary width, 1.42 μm, does not reach the barrier limit hindering diffusion, and the grain boundary diffusion coefficient D gb is 4.29 × 10 –14 m 2/s. At the beginning of holding at 1443 K (1170 ☌), the grain boundary diffusion between Mn and S belongs to interstitial diffusion. The diffusion of MnS in the δ + γ-Fe matrix is caused by volume diffusion and surface diffusion together, and the diffusion rate of Mn in the matrix phase D C is 2.90 × 10 –13 m 2/s and the volume diffusion rate D V,Mn is 1.89 × 10 –13 m 2/s. ![]() On the contrary, Mn is the diffusion controlling element. When the temperature is lower than 1343 K (1070 ☌), J S/ J Mn < 1, where S is the diffusion controlling element. It was first isolated in 1808 in England when Sir Humphry Davy electrolyzed a mixture of lime and mercuric oxide. Calcium was named after the Latin term calx meaning lime, and is a reactive silvery metallic element found in Group 2 of the periodic table. Sintering occurs through the coupling of grain boundary diffusion and surface diffusion. It is also the fifth most abundant dissolved ion in seawater. ![]() Diffusion includes volume diffusion, surface diffusion, and grain boundary diffusion. The sintering behavior of MnS includes two stages: diffusion and sintering. One atomic mass unit is equal to 1.66 x 10 -24 grams. The unit of measure for mass is the atomic mass unit (amu). ![]() Therefore this resulting atomic mass is calculated from naturally-occurring isotopes and their abundance. The MnS inclusions are precipitated at 1717 K (1444 ☌). Note that each element may contain more isotopes. In this study, the solid phase diffusion, grain boundary diffusion, and sintering densification of MnS in 416 stainless steels at hot rolling temperature were investigated by confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and theoretical analysis. MnS is an important strengthening phase for AISI 416 stainless steel with excellent processability, in order to explore the formation mechanism of long strip MnS inclusions. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |