(1. 清華大學(xué) 材料科學(xué)與工程系，北京 100084；
2. 西安交通大學(xué) 金屬材料 強度國家重點實驗室，西安 710049)
摘 要: 對爆炸復(fù)合雙層金屬板LY12/Cu和LY12/LY12中L-T取向角裂紋的疲勞擴展行為進行了對比性實驗研究和理論分析。結(jié)果表明，雙層金屬板的界面相性能、體積分?jǐn)?shù)及界面兩側(cè)材料的性能差異對層合板中角裂紋的疲勞擴展具有重要影響。對由不同金屬構(gòu)成的雙層復(fù)合板，角裂紋疲勞擴展過程中試樣兩側(cè)面的裂紋長度不同，并且隨著裂紋擴展其差距逐漸加大，但存在最大值Δac。當(dāng)兩側(cè)面裂紋長度差Δa<Δac時，兩側(cè)裂紋擴展速率不同；當(dāng)Δa≥Δac時，兩側(cè)裂紋擴展速率相同。對整個裂紋擴展過程可用Δac和其后任一側(cè)的裂紋擴展Δ K—da/dN曲線共同描述。
關(guān)鍵字: 金屬層合板；疲勞裂紋擴展；界面
double-layer metal laminates(Ⅱ)
——Angle crack
HE Jia-wen2, MA Ju-sheng1
（1. Department of Materials Science and Engineering,
Tsinghua University, Beijing 100084, China;
2. State Key Laboratory for Mechanical Behavior of Materials,
Xi′an Jiaotong Un iversity, Xi′an 710049, China）
Abstract:The angle crack fatigue growth behavior in two kinds of explosive bond ed double-layer metal composite plates (LY12/LY12, LY12/Cu) was investigated. The results indicate that the properties of the interface and the components have significant influence on the angle-crack fatigue growth. For double layer plates with different components, during the fatigue propagation, the crack lengths on two sides surface of the same specimen are not the same. Their difference Δa is increasing with the fatigue growing and has a maximum value Δac. The fatigue crack growth rates of two sides of the same specimen are not the same if Δa<Δac, and after Δa≥Δac, the fatigue crack growth rates are the same. The suitable characterization of the angle crack fatigue propagation in double layer laminates should combine the Δac with the curve of ΔK—da/dN of one side after Δa≥Δac.
Key words: metal laminate；fatigue crack propagation；interface
