本文關(guān)鍵詞：不同角度裂紋缺陷對(duì)材料動(dòng)態(tài)斷裂行為的影響　出處：《科學(xué)技術(shù)與工程》2016年28期 　論文類型：期刊論文

  更多相關(guān)文章： 焦散線 沖擊載荷 裂紋缺陷 動(dòng)態(tài)應(yīng)力強(qiáng)度因子 動(dòng)態(tài)斷裂韌度

【摘要】：采用新型數(shù)字激光動(dòng)態(tài)焦散線試驗(yàn)系統(tǒng),對(duì)含相互垂直和相互共線兩種裂紋缺陷介質(zhì)在沖擊載荷作用下的動(dòng)態(tài)斷裂行為進(jìn)行了研究。結(jié)果表明:在動(dòng)態(tài)沖擊載荷的作用下,邊裂紋缺陷處應(yīng)力集中程度遠(yuǎn)大于試件的內(nèi)部裂紋缺陷處應(yīng)力集中程度;當(dāng)裂紋從垂直內(nèi)部裂紋缺陷的端部再次起裂時(shí),表現(xiàn)為Ⅰ/Ⅱ復(fù)合型斷裂;起裂后,裂紋的斷裂模式很快由Ⅰ/Ⅱ復(fù)合型向Ⅰ型轉(zhuǎn)化;而對(duì)于內(nèi)部共線裂紋缺陷而言,裂紋的起裂和擴(kuò)展始終表現(xiàn)為Ⅰ型斷裂形式。當(dāng)內(nèi)部裂紋缺陷垂直于邊裂紋時(shí),內(nèi)部垂直裂紋缺陷對(duì)邊裂紋擴(kuò)展的裂紋尖端的應(yīng)力強(qiáng)度因子和裂紋擴(kuò)展速度均有抑制作用;且當(dāng)裂紋再次從內(nèi)部垂直裂紋缺陷處起裂后,裂紋的擴(kuò)展速度和應(yīng)力強(qiáng)度因子也較共線裂紋缺陷時(shí)的高;裂紋擴(kuò)展速度與裂紋尖端的動(dòng)態(tài)應(yīng)力強(qiáng)度因子呈正相關(guān)性。
[Abstract]:The new testing system for digital laser dynamic caustics, with mutually perpendicular and mutual collinear two kinds of crack defect medium under impact load dynamic fracture behavior was studied. The results showed that under dynamic impact loading, edge crack defect degree of stress concentration is far greater than the internal crack at the test piece shall be the stress concentration degree; when the crack from the end of the vertical internal crack initiation again, for I / II complex fracture; fracture initiation, fracture mode of crack quickly by 1 / 2 composite type to the type conversion; and for the defects of internal cracks, crack initiation and propagation always for type I fracture. When the internal cracks perpendicular to the edge of the crack, the internal defects of vertical cracks on the crack tip edge crack stress intensity factor and crack growth inhibition rate of both; and when the crack The crack growth velocity and stress intensity factor are also higher than the collinear crack defect when the crack starts from the internal vertical crack defect. The crack growth rate is positively correlated with the dynamic stress intensity factor at the crack tip.

【作者單位】： 中國礦業(yè)大學(xué)(北京)力學(xué)與建筑工程學(xué)院;
【基金】：國家自然科學(xué)基金資助項(xiàng)目(51374212,51134025)資助
【分類號(hào)】：O346.1
【正文快照】： 項(xiàng)目(51374212,51134025)資助天然巖體中存在著大量的節(jié)理、層理、孔洞等缺陷,在動(dòng)態(tài)載荷作用下,介質(zhì)往往由于缺陷所處的位置和角度的不同而表現(xiàn)出不同的斷裂特性;因此,研究沖擊載荷作用下多缺陷介質(zhì)中,缺陷的位置及其缺陷間的相對(duì)角度對(duì)材料動(dòng)態(tài)斷裂特性的影響具有重要的現(xiàn)實(shí)，

本文編號(hào)：1378211