超高强度铁基内生复合板的裂纹敏感性  

Crack Sensitivity of Deformation Induced In-situ Composite Plates with Ultra-High Strength

作　　者：荆天辅[1] 张静武[1] 付万堂 高明 

机构地区：[1]燕山大学材料工程学院,秦皇岛066004

出　　处：《物理测试》1997年第2期4-7,共4页Physics Examination and Testing

基　　金：国家自然科学基金(No 59681006)

摘　　要：用半椭圆表面裂纹试样单轴拉伸研究了塑性变形诱发Cr-Mo-V铁基内生复合板的力学行为。结果表明这种内生复合板在超高强度水平上对表面裂纹不敏感。屈服强度高于1500Mpa,裂纹相对面积达14％时,最大名义应力高于0.9σ_(0.2),断口、微观结构和透射电镜下的原位拉伸的观察分析表明,这种内生复合板的微观结构是由平行于轧面排列的加工硬化了的马氏体板条及弱化了的板条间界面构成,这种弱界面可缓解主裂纹前沿的应力,应变集中而使其强度潜力得到充分发挥。Crack sensitivity of deformation induced in-situ composite plates (DISC) were studied by uniaxial tensile test using semi-elliptical surface crack specimens. The results indicate that DISC plates are not sensitive to crack. When their yield strength (σ0.2) is above 1500Mpa and the relative area of crack up to 14%, the maximum avarage stress(σC) is higher than 0. 9 σ0.2. The observation and analysis of fracture appearance, microstructure and TEM in-situ tension reveal that the microstructure of DISC plates consists of work-hardened martensite Laths, which parallel to rolling plane, and micro weakened interfaces formed from the lath boundaries during cold rolling. These weakened interfaces have toughening effects of delamination and can fully display the strengthening capability of DISC plates.

关 键 词：塑性变形 内生复合 裂纹 铁基复合材料 

分 类 号：TB333.03[一般工业技术—材料科学与工程]