查询词典 acicular

Acicular ferrite microstructure in micro-alloyed steels, which nucleates around non-metallic inclusions, especially oxide inclusions, has high strength and good toughness and possesses strong grain-refining ability by itself. The ultra-fine grained steel with excellent weldability is likely to be produced by forming in materials a great number of fine and dispersive micro-inclusions which is helpful to induce AF to nucleate around them through oxide metallurgy technology.

微合金钢针状铁素体组织强度高、韧性好，在奥氏体晶内非金属夹杂物上诱导形核，具有很强的自身细化晶粒的能力，通过氧化物冶金技术控制钢铁材料形成大量细小、弥散，具有诱导AF形核能力的有益微夹杂物，有望获得焊接性能优良的超细晶粒钢。

The microstructure of hardened layer and formation mechanism were investigated.The microstructure of hardened layer consist of the completely hardened region and the transition region.The completely hardening region is composed of fine acicular martensites,residual austenites and a few dot-like carbonides.From surface to bottom in the hardened layer,the microstructure varies from fine to coar...

结果表明：采用适当的磨削参数可满足该钢所要求的淬火温度，进而获得适宜的淬硬层显微硬度和强化层深度；磨削淬火层由完全硬化区和过渡区组成；完全硬化区主要由细小针状马氏体组成，从表面到里层，组织形貌呈现&细→粗→细&的变化规律，其形成机理是热-力耦合作用影响磨削淬火过程中的奥氏体晶粒大小及其位错密度，并将直接影响转变后的马氏体组织形貌。

The results show that BS 460MPa grade reinforced bar can be produced all from Q235 or 20MnSi billet by the remained heat treatment process but the production cost of the former is lower. When the water pressure minishes, the intensities of reinforced bar reduce; the higher the temperature at the entrance of cooling bed is, the lower the intensities are. Therefore, the commendatory process parameters are that five stages coolers should be opened, water pressure should be all 1.8～2.0MPa and the temperature at the entrance of cooling bed of Q235 reinforced bar should lower than 650℃. The typical microstructure(Q235): the surface layer is tempered sorbite; the transition layer is pearlite and ferrite, and the partial ferrite is acicular; the core is pearlite and ferrite and the grain fineness is 8～10 grade. The yield strength is reduced by 10～20MPa after natural ageing and it can be simulated by artificial ageing(100℃×2h or 200℃×1h).

结果表明，Q235和20MnSi钢都可以利用余热处理工艺生产出性能合格的钢筋，但前者的生产成本较低；水压减小，钢筋强度降低，上冷床温度越高，强度越低，推荐5段水冷器全开，水压均为1.8～2.0MPa，Q235钢筋的上冷床温度应控制在650℃以下；钢筋典型的金相组织（Q235）表层为回火索氏体，过渡层为珠光体+铁素体且部分铁素体呈针状，心部为珠光体+铁素体，晶粒度8～10级；自然时效后屈服强度下降10～20MPa，用人工时效可以模拟自然时效，工艺是100℃×2h或200℃×1h。

First, by controlling the aqueous process parameters, such as type of bases, flow rate of air, mixing rate, acicular iron hydroxide nanoparticles with the length of less than 150nm, and the axial ratio of about 6～8 were finally synthesized.

1控制碱法制备针形铁黄的工艺参数，如碱的种类、通气量、搅拌转速等，制得针长50nm，轴比6～8的纳米粒子。

Through the methods of sol-gel, hydrothermal reaction and forced hydrolysis, iron oxide particles with cubic, spherical, spindle and acicular shape were prepared with adding different regulators of crystal growth, such as NaH2PO4, HEDP. And through the methods of complexing-precipitate and precipitate, copper oxide and power blue were prepared respectively.

通过水热法、溶胶-凝胶法分别制备出了纳米球形和立方形Fe_2O_3；采用强迫水解法，通过添加晶型控制剂NaH_2PO_4、HEDP分别制备出了纳米纺缍形和针形Fe_2O_3，通过络合沉淀法制备出纳米球形CuO，通过沉淀法制备出纳米Co_2O_3。

The effect of addition rare-earth metal,Ca and Mg elements on the microstructure,toughness of and the formation of intragranular acicular ferrite in hot affect zone of large heat-input welded low alloy non quenched-tempered steel plate was investigated.

研究了低合金高强度非调质中厚板钢中添加稀土和Ca、Mg微量元素对大线高能焊接热影响区显微组织微细化和晶内针状铁素体形成的影响。

This paper introduced X70 and X80 HRC with heavy thickness which were designed by low carbon, high niobium acicular ferrite microstructure , and developed on medium thickness slab continuous casting production line in Ansteel.

介绍了鞍钢股份有限公司采用低碳高铌针状铁素体组织设计、在中等厚度连铸坯连铸连轧生产线上研制开发特厚规格X70和X80级管线钢热轧卷板的情况。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。