Metallurgical and Materials Transactions a-Physical Metallurgy and Materials Science
Stress corrosion cracking (SCC) behavior of three kinds of low alloy pressure vessel steels in high-temperature (200 degrees C to 300 degrees C) caustic aluminate (AlO2-) solutions has been studied by slow strain rate tests (SSRT). The results indicate that these pressure vessel steels are susceptible to SCC in caustic aluminate solution and that the SCC susceptibility increases with increasing temperature between 200 degrees C to 300 degrees C. Sulfide content and stringered sulfide inclusions severely and anisotropically affect the caustic SCC of these low alloy steels. The inclusions in the rare-earth-treated steel are predominantly globular rare-earth sulfides or oxysulfides, resulting in improved transverse properties. The effect of inclusions on SCC behavior correlates with the projected area of inclusions per unit volume at the crack tip, A(nu), on the plane perpendicular to the tensile direction. The susceptibility to SCC increases with increasing A(nu).
关键词:
behavior
Journal of Materials Science
A new technique has been developed which aims at changing the form of bamboo from its natural circular cross-section into a plate for convenient use. The manufacturing technique covers three major processes: softening, compression and fixture. The microstructure of reformed bamboo was studied both qualitatively and quantitatively. The mechanical properties of reformed bamboo were tested and the results show a remarkable increase compared with normal bamboo. Although the reformed bamboo has many advantages, such as higher specific properties, inexpensive cost, etc., the composition of reformed bamboo with aluminium alloy sheets further improves the comprehensive performance.
关键词:
behavior
Materials Science and Technology
Electromagnetic stirring using multiple induction coils has been investigated as a method of preparing semisolid FC20 alloy. The effects of additions of titanium, zirconium, and boron on the microstructure of the FC20 alloy have also been studied. The electromagnetic flux density increased with input voltage and was higher at the wall of the container than near the centre of the coil. The microstructure of the alloys varied with cooling rate: the higher the cooling rate, the smaller the particle size and the greater the degree of sphericity. The additions of titanium, zirconium, and boron also improved the alloy microstructure. (C) 2001 IoM Communications Ltd.
关键词:
behavior
李飞
,
琚红亮
,
杨亚波
,
李云
,
张国范
电镀与涂饰
总结了电镀生产中操作标准化和管理标准化方面的经验,介绍了一些标准化的操作行为和操作手法(包括带电入槽、抖动工件和清洗)、列举了一些员工培训及工艺控制方面实施标准化的例子.
关键词:
电镀
,
操作
,
行为
,
手法
,
工艺控制
,
培训
,
标准化
吕沙
,
吴光亮
钢铁
doi:10.13228/j.boyuan.issn0449-749x.20140492
对采用“EBT→LF→VD”工艺路线生产50Cr5MoV锻钢轧辊炼钢过程的全氧质量分数和夹杂物类型与数量进行了分析。结果表明：LF精炼后钢液中w(T[O])平均为0.0047%，VD出站w(T[O])为0.0014%，中间包w(T[O])为0.00155%，铸坯w(T[O])为0.0018%，轧材中w(T[O])降低至0.0010%。LF精炼初期，钢中夹杂物主要是不规则的Al2O3夹杂，其中96.75%的夹杂物尺寸小于10μm。LF精炼结束后，大量夹杂物转变成以CaO-Al2O3-SiO2为主要成分的0～10μm复合氧化物夹杂。钢水从VD真空精炼炉向中间包转移过程中，由于保护性浇注效果差，二次氧化严重造成钢水夹杂逐渐增多，其中夹杂物主要为球形的mCaO·nAl2O3复合夹杂物。铸坯中99.65%的夹杂物尺寸小于10μm，其中大部分为球形钙铝酸盐夹杂物，还有少量球状硅铝酸钙复合夹杂物。轧材中98.77%的夹杂物尺寸小于10μm。通过对炼钢过程中各工序的工艺优化，可实现对夹杂物的有效控制，从而确保50Cr5MoV合金铸钢的产品质量。
关键词:
50Cr5MoV钢
,
夹杂物
,
行为
,
全氧质量分数
