共搜索到1368条信息，每页显示10条信息，共137页。用时：0小时0分0秒330毫秒
微合金钢中强化相时效析出行为的内耗研究曾犇1,吴静1,沈斌1,张恒华1(1.上海市上海大学材料科学与工程学院)摘 要:将微合金钢在1200℃固溶1 h后水淬至室温,部分固溶态试样再经过700℃时效5,240 min,然后应用强迫振动法测量微合金钢的内耗值,其中内耗测温范围为室温至430℃.内耗试验结果表明:在109℃产生的Snoek峰是碳原子微扩散引起的内耗峰,该峰随着时效时间的延长,峰值逐渐减弱且不偏移,时效240 min后该峰消失,主要是因为在时效过程中碳原子与合金元素形成碳化物以沉淀形式析出,从三维原子探......
......
......
, 1684613114, Iran)Abstract:the fatigue behavior, indirect tensile strength (ITS) and resilient modulus test results for warm mix asphalt (WMA) as well as hot mix asphalt (HMA) at different ageing levels were evaluated. Laboratory-prepared samples were aged artificially in the oven to simulate short-term and long term ageing in accordance with AASHTO R30 and then compared with unaged specimens. Beam......
大三级时效的回归时间窗口,降低回归温度,可使合金同时获得更优异的强度和耐蚀性能. 关键词:Al-6.2Zn-2.3Mg-2.3Cu铝合金；时效制度；电化学腐蚀；腐蚀形貌 中图分类号:O646.6 文献标志码:A Effect of ageing... performed in 3.5% (mass fraction) NaCl and 10 mmol/L NaCl+0.1 mol/L Na2SO4 solutions. The results show that the resistance to localized corrosion of various ageing processes according to decreasing order......
航空有机玻璃紫外光老化研究 裴高林1,陈新文1,金玉顺2 (1.北京航空材料研究院,北京,100095;2.北京石油化工学院,北京,102617) 摘要:对YB-DM-11航空有机玻璃试样在254nm和313nm两种波长的紫外光照射下,进行了2个月的加速老化试验,跟踪测试了有机玻璃的抗拉强度和重量变化规律.通过红外光谱(FTIR),热分析(TG/DTA),扫描电镜(SEM)和凝胶渗透色谱(GPC)等方法,分析了老化前后试样的结构和性能,结合老化前后有机玻璃的性能变化规律,揭示了有机玻璃在紫外光照射下的老化机理. 关键词:有机玻璃; 紫外光; 加速老化; 老化规律; 老化机理; perspex(PMMA); ultraviolet; accelerated ageing; ageing rule; aging mechanism; [全文内容正在添加中] ......
: Al-Zn-Mg-Cu alloys; ytterbium; mechanical properties; stress corrosion cracking; ageing ... at 480 ℃ for 2 h for further solution treatment, then were quenched by cold water. The samples were tempered artificially with T6 and T77 treatment, respectively. Ageing process of all samples......
......
precipitates are δ′, θ′ and T1 phases. While under T8 peak aged condition, the major precipitates contain δ′ phase, T1 phase and θ′ phase with small volume fractions. The pre-stretching prior to ageing promotes the precipitation of T1 phase, thus improves ageing strengthening. Mg addition promotes the precipitation of GP zone and θ′ phase while Zn facilitates T1 phase precipitation. The addition of Mg......
Effect of Lüders Bands by Strain Ageing on Strain Distribution, Microstructure and Texture Evolution of High-Strength Pipe SteelJian Han1,Jun Wang2,Sunusi Marwana Manladan3,Yangchuan Cai1,Qian... loading of the specified tension samples, the migration behaviour of Lüders bands and the re-distribution of stress after strain ageing heat treatment were investigated using digital image correlation......
