25MnV钢零保温奥氏体逆相变淬火

采用正交组合回归设计试验方法，研究了二次零保温淬火温度对25MnV钢强度和硬度的影响，分析了该钢零保温奥氏体逆相变淬火后的组织与性能.试验表明：25MnV钢在830~930 ℃零保温奥氏体逆相变淬火，得到极细的板条状马氏体组织.在试验的温度范围内，830 ℃淬火，该钢的组织最细.随淬火温度的升高，组织粗化，强硬性降低.低温零保温奥氏体逆相变淬火，可显著提高该钢的力学性能.     

Cu-Cr-Zr-Mg合金的变形时效行为

通过对Cu-0．3Cr-0．15Zr-0．05Mg合金硬度、导电率分析和显微组织观察。研究冷变形和时效处理对合金组织和性能的影响。结果表明，冷加工变形产生的位错。加速Cu-0．3CF0．15Zr-0．01Mg合金的时效过程。大幅度提高合金的导电率和硬度．在时效的初期尤为明显。合金固溶并80％形变后在470℃时效2h导电率和硬度分别达75．1％IACS和156．1Hv，60％变形500℃时效0．5h导电率和硬度分别达73．3％IACS和165．7Hv。     

复杂条件下挡墙的设计及地基加固技术

结合具体工程实践，针对工程中的复杂地质条件和环境条件，对超高挡土墙的设计进行了分析，并依据挡墙不同部位的土质特点采用不同挡墙地基方法进行加固处理，观测结果表明该设计和施工方案是安全合理的。     

岩石在酸化环境下的强度损伤及其静态加速模拟

在不同质量百分比(1.0%,5.0%及10.0%)的3种酸溶液(H2SO4,HNO3和HCl)中,对大理岩和辉绿岩的水岩作用进行了静态长时(900d)加速浸泡试验模拟,分析了岩石单轴抗压强度、劈裂法抗拉强度和表面肖氏硬度的损伤对酸的敏感性和损伤机制。研究结果表明,在静水环境下,岩石强度损伤、硬度损伤及腐蚀速率与H 浓度及浸泡时间成非线性关系,岩石腐蚀所产生的环境效应不仅与岩性、酸种和H 浓度有关,而且与新成盐是否发生水解有关。     

湿陷性黄土的抗剪强度

在室内对不同含水量和不同前期饱和固结压力的黄土进行直剪试验,同时对黄土横、纵向的抗剪强度进行了研究,发现含水量、前期饱和固结压力对抗剪强度的影响较大,而横、纵向的抗剪强度差别很小。     

浅谈膨胀土路基的施工技术

对沟张和周沟两个膨胀土场做了素土试验,针对其结果进行了外掺生石灰粉改性试验,较好地消除了其膨胀性,通过某高速路膨胀土路基的施工,阐述了其施工中采用的具体技术与措施,实践证明,采用外掺石灰粉用于改性膨胀土是经济的、可行的。     

对20Cr钢进行WC激光表面合金化的研究

利用多种技术手段对20Cr 钢 WC 激光表面合金化问题进行了分析测试,考核了处理后材料的表面硬度及表层耐磨性,并对材料经激光表面合金化后的显微组织、组成物相、成分分布及强化机制做了较为深入的分析和探讨,实验结果表明,20Cr 钢 WC 激光表面合金化后表面综合机械性能大幅度提高,是一种有效的表面强化手段。     

自干型水溶性醇酸树脂的配方设计

建立了适合于水溶性醇酸树脂配方设计的通用程序。讨论了醇酸树脂的基本参数K、油度L、醇超量R及酸值Sv对醇酸树脂干燥时间和硬度的影响。结果表明当K=1、L=50%、R=1.2时,醇酸树脂膜有最短的干燥时间,所得膜的硬度也最高;Sv越大,干燥时间越长,但是膜的硬度越大。     

The behaviour of phosphate, nitrate, chloride and hardness in twelve welsh rivers

Selected water quality data from 12 rivers in the area administered by the Welsh Water Authority were analysed for the period 1974–1981. Mean nitrate-nitrogen concentrations varied from 0.4 to 3.7 mg l⁻¹ and were significantly related to the intensity of average catchment run-off; mean orthophosphate-phosphorus concentrations ranged from the limit of analytical detection to 0.730 mg l⁻²; chloride from 11 to 42 mg l⁻¹ and total hardness (as CaCO₃) from 13 to 173 mg l⁻¹. Seasonal patterns of change in concentration were established, generally for all determinands at most sites, but no long-term trends were detected. Relationships between concentration and flow were established for most determinands at many sites, increasing flow generally resulting in decreased concentration. However, positive relationships between nitrate concentration and flow were established at seven sites. Mass flows (kg ha⁻¹ yr⁻¹) were calculated at nine sites only: nitrate-N 4.8–24.6; orthophosphate-P 0.16–3.81; chloride 79–334; total hardness (as CaCO₃) 196–1629. Orthophosphate flows were related to sewered population density, estimates of per capita and land drainage contributions being 1.9 g day⁻¹ and 0.112 kg ha⁻¹ yr⁻¹ respectively.     

30CrNiMo高强钢可焊性研究

采用焊接热影响区最高硬度试验法、T型接头焊接热裂纹试验法、斜Y型坡口焊接冷裂纹试验法和对接接头刚性拘束焊接裂纹试验法,对30CrNiMo高强钢进行工艺焊接性和抗裂性能综合评定。结果表明:焊接热影响区最高硬度HV值在545左右,15 mm厚高强钢板各种裂纹试验焊接接头区域均未发现裂纹;30CrNiMo高强钢对焊接冷裂纹较敏感,焊接时需要考虑预热或后热处理,经优化后的15 mm厚30CrNiMo高强钢具有较高的抗焊接裂纹敏感性。