钛锆复合脱氧对高强度低合金钢机械性能的影响.pptxVIP

The Effect of Ti-Zr Deoxidation on the Mechanical Properties of High Strength Low Alloy Steels Outline● Introduction● Purpose● Experimental● Results and discussion● ConclusionIntroductionAlthough carbides and nitrides play an important role in precipitation strengthening and particle pinning, oxides have other advantages because they tend to be more stable than carbides and nitrides in steels. This is particularly true when steels undergo high heat input welding. Many studies have been reported on the application of Zr in steels, such as the effects on austenite grain growth control, sulphide shape control, and improving both transverse toughness and weldability. However, very few works have investigated the effects of combined oxidation on the mechanical properties. Purpose●The stability of the mechanical properties, especially elongation and impact toughness, were compared between steel A, which was deoxidized with Ti-Zr, and steel B, which was deoxidized with Al. ● This aims to study the effects of combined oxidation of titanium and zirconium on the mechanical properties of high strength low alloy steels.ExperimentalTable 1 The chemical composition of the investigated plates (wt.%)CMnSiPS0.04-0.071.55-1.680.20-0.30?0.015?0.002Nb+TiNi+ Cr+ MoBCaN0.06-0.080.60-0.800.0012-0.00200.0008-0.0035?0.006baResults and DiscussionMicrostructures Fig. 1 Optical microstructures of Steels A (a) and B (b)The type and size of oxides Fig. 2 TEM-EDS image of the typical oxide in Steel AFig. 3 The size distribution of inclusions in Steel A and Steel B M/AMembranous M/AOxidesbcedfaFig. 4 The sub-micron and nano-sized inclusions in Steel A(a) oxided on interface (b) and (c) oxides in the matrix Dispersed distribution of MnS Fig. 5 The fracture surface with inclusions in the dimples, and the EDS spectrumbaFig. 6 Optical micrographs of inclusions in (a) Steel A and (b) Steel B Mechanical properties Fig. 7 Distribution of mechanical properties of Steel A and B(a) Yield strength and tensil