钢可淬性的计算机模拟

对于给定的钢、碳曲线和工艺条件,可淬性模型可预告渗碳或完全淬火零件的显微组织和硬度分布。与扩散模型不同,它是以固定距离增量将零件表面层划分成固定数目的节点,在可淬性模型中,将平面或圆面看作为一维截面,以可变距离增量分成20个节点。

机床导轨淬硬性的试验研究

在碳当量（ＣＥ）３．７％～４．０％范围内，探讨了影响机床导轨淬火硬度的组织因素和改善途径。结果表明，珠光体含量和片层间距是影响导轨硬度的主要因素。提高硅碳比，不能有效提高导轨硬度，使用冷铁易引起淬火裂纹，采用Ｓｂ－ＲＥ－Ｃａ复合处理，可获得较好的导轨性能，铸态硬度≥ＨＢ２００．淬火态硬度≥ＨＲＣ４５。

Coordinate Bond Breaking Induced by Collapse of Poly(N-isopropyl acrylamide) as Ligands of a Rare Earth Complex

A novel water-soluble luminescent complex consisting of Eu(ally-dbm)3-2Tppo and poly(N-isopropyl acrylamide)(PNIPAM)is synthesized through a series of chemical reactions.The structure of the complex is characterized by TGA,GPC,HNMR,and the thermal-responsive uorescence of the complex in aqueous solution is investigated.It is found that PNIPAM collapse above the lower critical solution temperature causes the coordination bond breaking,leading to weakening of the uorescence from Eu3+and enhancing of the uorescence from the ligands.When temperature decreases,the uorescence from Eu3+is found to boost up and the uorescence from ligands weakens accordingly.It is deduced from this phenomenon that the ligands recoordinate with europium ions again along with the temperature decreasing,which is further confirmed by IR measurements.This thermal-responsive uorescence is of reversibility,which can be used as molecular probes for biological imaging and collapse studying of PNIPAM.

无镍P／M钢硬度高、强度大

美国Hoe ganaes公司开发出一种无镍P／M钢，其中含有铬、锰、硅和钼。向锻钢中加入大量铬和锰以改善其力学性能和可淬性。由于这些元素易于氧化，因而不易掺到P／M钢中去。但是烧结研究表明，适量的含氧量并不影响良好的力学特性。