耐腐蚀摩托艇ADC12-0.5La铝合金微观组织及制备

为改善ADC12铝合金的耐腐蚀性能,通过超声熔铸法制备ADC12-0.5La铝合金,并利用光学显微镜、扫描电镜、能谱分析仪、硬度计、浸泡腐蚀试验和电化学工作站研究了T6热处理和稀土La改性对ADC12铝合金的微观组织、硬度和耐腐蚀性能的影响。结果表明,T6态ADC12-0.5La铝合金微观组织明显细化,α-Al尺寸减小,形貌变圆整,共晶Si相和AlFeMnSi相细化为短棒状。相比于ADC12铝合金,T6态ADC12-0.5La铝合金硬度达到117.7HV,提高了26.8%,腐蚀电流密度降低了10.7%,腐蚀电位上升了64.4%,腐蚀速率降低了54.4%,腐蚀表面平坦且光滑,表现为较轻微的晶间腐蚀。T6态ADC12-0.5La铝合金提高了腐蚀电位,Al-La-Cu稀土相阻碍了电子移动,铝合金的耐腐蚀性能得到大幅度提高。     

Characterization of blasted austenitic stainless steel and its corrosion resistance

It is known that the corrosion resistance of stainless steel is deteriorated by blasting, but the reason for this deterioration is not clear. A blasted austenitic stainless steel plate (JIS-SUS304) has been characterized with comparison to the scraped and non-blasted specimens. The surface roughness of the blasted specimen is larger than that of materials finished with #180 paper. A martensite phase is formed in the surface layer of both blasted and scraped specimens. Compressive residual stress is generated in the blasted specimen and the maximum residual stress is formed at 50–100 μm from the surface. The corrosion potentials of the blasted specimen and subsequently solution treated specimen are lower than that of the non-blasted specimen. The passivation current densities of the blasted specimens are higher those of the non-blasted specimen. The blasted specimen and the subsequently solution treated specimen exhibit rust in 5% sodium chloride (NaCl) solution, while the non-blasted specimen and ground specimen do not rust in the solution. It is concluded that the deterioration of corrosion resistance of austenitic stainless steel through blasting is caused by the roughed morphology of the surface.     

Zr41.5Ti14Cu13Ni10Be22.5大块非晶的耐蚀性能

用浸泡法研究了ZrTiCuNiBe大块非晶合金在酸、碱、 盐各种腐蚀性介质中的腐蚀行为.并与典型材料做了比较，结果表明：ZrTiCuNiBe大块非晶合金具有良好的耐蚀性.     

FORMATION OF MANGANESE SILICIDE THIN FILMS BY SOLID PHASE REACTION

1. IntroductionThe transition metal silicides have attraeted much attention because of their potentialapplicatiOIl in very large scale integration (VLSI) de.ice[1]. Near-noble metal silicides canbe used as Schottky al1d ohn1ic col1tacts in silicon-based d…     

电感电容损耗电阻的讨论

通过对电容电感阻抗的测量，发现实验值偏离理论值。定性地分析了误差的来源，得出的结论是电感电容内部的损耗电阻随着频率的变化而变化，变化方向相反而并非相同。     

用正交实验设计研究Zr—Nb合金的耐蚀性

利用正交设计实验的方法安排了一组Ｚｒ－Ｎｂ二元合金，考查了两个水平的Ｎｂ含量，淬火温度，时效温度，时间以及合金组织状态对耐蚀性能的影响，５００℃蒸汽腐蚀结果表明，Ｎｂ含量控制在固溶极限范围内Ｚｒ－Ｎｂ二元含金具有较佳的耐蚀性，而当Ｎｂ含量较高时，采用双相区淬火，较高温度长时间时效处理是获得较好耐蚀性的工艺方向。     

提高高铬白口铸铁磨球冲击抗力的技术关键

当高铬白口铸铁含铬量为18%～28%,Cr/C值是8￣9,铸铁的显微组织是回火马氏体 少量残余奥氏体(<5%) M7C3碳化物,则磨球具有高的冲击韧性和断裂韧性K1C,具有高的冲击抗力,表现出低的冲击剥落量。     

等温淬火球铁在铁道车辆耐磨件上的应用研究

考虑到等温淬火球铁具有强度高、韧性好、出色的耐磨性等优点，根据铁道车辆斜楔和衬套配件的服役要求，对等温淬火球铁和传统的金属材料进行了大量摩擦磨损性能比较试验，结果表明，等温淬火球铁斜楔和衬套具有比传统材料高得多的耐磨性，特别是等温淬火球铁斜楔的使用寿命是以往ZG230-450斜楔的6～10倍。因此，等温淬火球铁斜楔和衬套件已在我国铁路车辆上得到了广泛应用。     

三石─堇青石匣钵的研制

引入“三石”改善堇青石质匣钵性能,提高匣钵使用寿命。     

Effects of extreme floods on macroinvertebrate assemblages in tributaries to the Mohawk River,New York,USA

Climate change is forecast to bring more frequent and intense precipitation to New York which has motivated research into the effects of floods on stream ecosystems. Macroinvertebrate assemblages were sampled at 13 sites in the Mohawk River basin during August 2011, and again in October 2011, following historic floods caused by remnants of Hurricane Irene and Tropical Storm Lee. The annual exceedance probabilities of floods at regional flow‐monitoring sites ranged from 0.5 to 0.001. Data from the first 2 surveys, and from additional surveys done during July and October 2014, were assessed to characterize the severity of flood impacts, effect of seasonality, and recovery. Indices of total taxa richness; Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness; Hilsenhoff's biotic index; per cent model affinity; and nutrient biotic index‐phosphorus were combined to calculate New York State Biological Assessment Profile scores. Analysis of variance tests were used to determine if the Biological Assessment Profile, its component metrics, relative abundance, and diversity differed significantly (p ≤ .05) among the four surveys. Only total taxa richness and Shannon–Wiener diversity increased significantly, and abundance decreased significantly, following the floods. No metrics differed significantly between the July and August 2014 surveys which indicates that the differences denoted between the August and October 2011 surveys were caused by the floods. Changes in taxa richness, EPT richness, and diversity were significantly correlated with flood annual exceedance probabilities. This study increased our understanding of the resistance and resilience of benthic macroinvertebrate communities by showing that their assemblages were relatively impervious to extreme floods across the region.