Crystalline Behavior and Magnetic Properties of Nd60Fe30-x Al10Cox（x = 0,5,10） Bulk Amorphous Alloys

Crystalline behavior and magnetic properties of Nd60Fe30-xAl10Cox( x = 0, 5, 10) bulk amorphous alloys were investigated by differential scanning calorimeter (DSC), X-ray diffraction (XRD) and the vibrating sample magnetometer (VSM). Neither glass transition nor supercooled liquid region before crystallization was observed for the as-cast Nd60Fe30-xAl10Cox ( x = 0,5,10) bulk amorphous alloys. The glass forming ability can be improved significantly by the addition of Co. The as-cast Nd60Fe30-xAl10Cox (x = 0,5,10) alloys show hard magnetic behavior. With the addition of Co content, intrinsic coercivity (iHc) increases while the saturation magnetization(σs) and remanence (σr) decrease. The Curie temperature for the as-cast Nd60Fe30-xAl10Cox alloys increases from 451 K for x =0 to 468 K for x = 10. Some pre-cipitation of crystalline phases does not affect the hard magnetic properties of Nd60Fe30-xAl10Cox(x = 0,5,10) alloys, while the hard magnetic behavior disappears quickly after the alloys being completely crystallized.     

Alleviation Effect of Lanthanum on Cadmium Stress in Seedling Hydroponic Culture of Kidney Bean and Corn

Since1970s,rare earths(RE)have been exten-sively used as micro-fertilizers for crops in China.Ithas already been proved that REcani mprove the pro-duction and quality of crops.However,there havebeen a fewinvestigations about using RE as regulatorin pollution ecology.For example,An et al[1]studiedthe effects of O3on wheat growth and the protectiveeffect of RE.Yan and Zhou et al[2,3]discussed theprotective effect of RE on plants under acid rainstress.Jia et al[4]and Hu et al[5]reported th…     

HDA-1特种不锈钢焊条的研制及应用

以不锈钢焊丝作焊芯，通过药皮过渡某些合金，用常规方法制造一种特殊焊条。焊层金属为铁素体 奥氏体双相组织，具有良好的抗裂性和抗高温(900—1200℃)氧化性能，特别耐含S气氛的高温氧化。经用户在镁还原罐上两年多的使用，获得了理想的效果。     

Hydrogen Absorption and Release Behavior in Hydrogen Decrepitation Process of Nd-Fe-B Alloys

The behavior of hydrogen absorption and release in hydrogen decrepitation (HD) process of Nd-Fe-B alloys were investigated. The results reveal that the reactivity and the amount of hydrogen absorption in HD process are related to the surface activity of the alloy so that the fresh and active surface has a higher efficiency. The presence of Nd-rich phase at the grain boundary is an essential factor of the HD activity of the alloy at room temperature. On degassing, hydrogen is released from the HD powder continuously with increasing temperature. And the residual hydrogen is as low as 0.0015% at 1073K, which shows that the hydrogen is almost exhaused. It is feasible to remove the hydrogen from the HD powder by heating treatment at the temperature of 523-723K for 1h prior to the magnetic field forming in order to decrease the harmful effect of hydrogen on the easy axis alignment of HD magnet.     

“呼吸道吸入天然钍（ThO2）和稀土矿尘联合作用的研究”（1987～2002）2003年获奖

由中国疾病控制中心辐射防护和核安全医学研究所(原卫生部工卫所)及协作单位包钢白云鄂博矿职工医院共同完成的“呼吸道吸入天然钍(ThO2)和稀土矿尘联合作用的研究”项目，获2003年度北京市科学技术奖二等奖。     

γ＋β两相TiAl化合物的超塑性

γ-TiAl金属间化合物重量轻,高温强度及抗蠕变性能好,是有希望的高温结构材料,但其低温塑性差,难加工成型,是当前急需研究解决的问题之一.超塑成型是加工成型这类材料的常用手段.γ-TiAl金属间化合物晶粒细化也是超塑成型的重要条件.γ-TiAl中混有α2相可使其组织细化,从而实现超塑成型.热加工时,α或β等高温相可能同时存在,特别是β相具有高变形能力,这样的混合组织是更有利于加工变形的,所以向γ-TiAl化合物中添加铬,可使其合金含有β相,从而产生了超塑性现象.