共查询到15条相似文献,搜索用时 163 毫秒
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统计分析了28组采用TMCP工艺制造的高强度厚钢板-10℃止裂韧性K_(ca)与屈服强度R_(P0.2)、抗拉强度R_m、-40℃冲击功KV_2、-20℃和-40℃动态撕裂能DTE、零塑性转变温度T_(NDT)的相关性规律,结果表明,-10℃止裂韧性K_(ca)与心部抗拉强度R_m和侧面零塑性转变温度T_(NDT)的相关度较高,随着心部抗拉强度R_m的增高和侧面零塑性转变温度T_(NDT)的降低,-10℃止裂韧性K_(ca)增大;在此基础上建立了-10℃止裂韧性K_(ca)与心部抗拉强度R_m、侧面零塑性转变温度T_(NDT)和板厚t的相关性方程K_(ca)=13.358·R_m-90.530·T_(NDT)-7.324·t~(1.5)或K_(ca)=13.427·R_m-74.845·T_(NDT)-0.635·t~2。 相似文献
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按照GB/T 228.1—2010中推荐的不同拉伸速率控制模式及拉伸速率对冷轧镀锌钢板进行了拉伸对比试验,分析了应变速率、横梁位移速率及应力速率对冷轧薄板规定非比例延伸强度Rp0.2、下屈服强度R以及抗拉强度Rtn测试结果的影响。结果表明:采用应变速率进行控制得到的拉伸试验数据相对其他两种速率控制模式更为稳定,可以最大限度地降低拉伸测试结果的不确定度;采用0.000 25 s-1的应变速率控制模式所得试验结果的稳定性与采用40~50 MPa·s-1的应力速率控制模式所得结果较为接近;在不同拉伸速率控制模式下,提高应变、横梁位移和应力速率均会使屈服强度Rp0.2和Rel增加,而抗拉强度Rtn基本上处于稳定状态。 相似文献
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对梯温型宽板拉伸止裂试验中的止裂韧性K_(ca)、止裂温度T_K、止裂应力σca的相关性规律进行了理论分析,结果表明,相同温度下的止裂韧性和止裂应力呈线性关系,其线性系数由试板宽度Ws、温度场参数(T150、GT)和温度T_K确定;对21组试验数据的统计分析结果验证了该相关性规律。 相似文献
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微薄板塑性成形本构关系研究 总被引:1,自引:0,他引:1
尺寸效应的影响使得传统的成形理论和变形机制不再适用于微塑性成形.在考虑尺寸效应对微薄板成形性能影响的基础上,对已有的CuZn36黄铜薄板微拉伸实验结果进行处理,提出了一种研究微塑性成形本构关系的方法.根据弹性和塑性变形过程,分阶段分析了t/d(板厚/晶粒大小)对屈服强度和切线模量的影响,修正了双线性弹塑性本构关系,获得了考虑尺寸效应的微塑性成形本构关系.借鉴宏观增量本构关系,结合微拉伸实验,采用Mises屈服准则和随动强化模型,得出适合微塑性成形的弹塑性增量本构方程,为微塑性成形的理论研究和实际应用奠定了基础. 相似文献
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Isamu Oda 《Engineering Fracture Mechanics》1988,29(6):663-671
Correlation between the Charpy absorbed energy and critical COD is investigated to obtain a useful method for estimating critical COD from Charpy V data. The round bar tension test, Charpy V-notch test and static 3-point bend test with fatigue notched specimen are carried out using mild steel, 785 MPa grade high strength steel and A5083 aluminum alloy. Correlation is found between W'c/σY and δc as well as between EW'c/σY2 and Eδc/σY, where W'c is the Charpy absorbed energy obtained by considering temperature difference between the Charpy transition temperature and COD transition temperature. The symbols σY, δc and E are yield strength, critical COD and Young's modulus, respectively. The correlations are established for various kinds of metals and over a wide temperature range including not only upper shelf range but also the transition range. 相似文献
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The influence of structural dimensions on crack arrest 总被引:1,自引:0,他引:1
A.H Priest 《Engineering Fracture Mechanics》2003,70(17):2421-2437
An energy balance has been used for the prediction of toughness values required to ensure arrest in double tension crack arrest tests. The analysis required calculation of the total energy that depended on the force applied to the main plate and the effective length of the structure including the test frame. Theoretical calculations indicated that the energy release rate at crack arrest was governed by both the width and the length of the structure
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The crack arrest fracture toughness of two high strength steel alloys used in naval construction, HSLA-100, Composition 3 and HY-100, was characterized in this investigation. A greatly scaled-down version of the wide-plate crack arrest test was developed to characterize the crack arrest performance of these tough steel alloys in the upper region of the ductile-brittle transition. The specimen is a single edge-notched, 152 mm wide by 19 mm thick by 910 mm long plate subjected to a strong thermal gradient and a tensile loading. The thermal gradient is required to arrest the crack at temperatures high in the transition region, close to the expected service temperature for crack arrest applications in surface ships. Strain gages were placed along the crack path to obtain crack position and crack velocity data, and this data, along with the applied loading is combined in a “generation mode” analysis using finite element analysis to obtain a dynamic analysis of the crack arrest event. Detailed finite element analyses were conducted to understand the effect of various modeling assumptions on the results and to validate the methodology compared with more conventional crack arrest tests.Brittle cracks initiation, significant cleavage crack propagation and subsequent crack arrest was achieved in all 15 of the tests conducted in this investigation. A crack arrest master curve approach was used to characterize and compare the crack arrest fracture toughness. The HSLA-100, Comp. 3 steel alloy had superior performance to the HY-100 steel alloy. The crack arrest reference temperature was TKIA = −136 °C for the HSLA-100 plate and TKIA = −64 °C for the HY-100 plate. 相似文献
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H. Mimura 《Fatigue & Fracture of Engineering Materials & Structures》1995,18(6):699-705
Abstract The present paper proposes possible mechanisms to explain the following experimental facts reported in the literature.
- 1 Fracture toughness has little dependence on plate thickness in the low temperature range.
- 2 In some steels, crack initiation sites are much closer to the crack tip than predicted in the transition temperature range by current theory.