风沙流中沙粒冲击速度的分布函数

根据风沙流通量和速度随高度的变化推导出了风沙流中沙粒冲击速度的分布函数,与以往建立的风沙流中起跃沙粒垂直初速度的分布函数稍有不同。用最新引进的粒子动态分析仪对53000多个沙粒冲击速度的风洞验证结果表明,所建立的冲击速度的分布函数与风洞实验结果吻合得相当好,80％以上的拟合相关系数大于0.95。     

Analysis of chemical composition of melt inclusion of beryl in pegmatite and discovery of zinc-spinel by electronic probe

The compositions of daughter mineral of melt inclusion in beryls, which are from pegmatite of Keketuhai in Xinjiang and Mufushan in Hunan, have been analyzed by electronic probe. Ten kinds of mineral, such as beryl, zinc-spinel, mica, quartz, magnetite, etc., which consist of different mineral associations have been identified. The zinc-spinel existing in two different forms was first discovered in the melt inclusion in China and abroad. This study provides that there exist the local magmatic differentiation and the immiscibility and heterogeneity of magma. It is very useful for the current research of magmatic rocks, pyrolite, meteorolite.     

Experimental studies on silicate structures of basaltic glasses quenched at 1 65093 and 1–3.5 GPa

A series of melting experiments was carried cut at 1 650°C and 1.00–3.00 GPa using alkaline basalt as starting material. The cornpitions of quenched basaltic glasses in the products were detected by electron micro probe. Their CIPW norms were calculated and their refractive indices were determined by the oil-infused method. The Raman spectrum of the quenched basaltic glasses indicates that their main structural species are monomer [Si₂O₄]1⁴⁻, chain [Si₂O₆]1^4- and sheet [Si₂O₅]1^2-. The relationship at the same temperature between the proportions of integrated areas of structural species, and compositions and pressures was discussed.     

Experimental studies on silicate structures of basaltic glasses quenched at 1 650℃ and 1-3.5 GPa

A series of melting experiments was carried out at 1 650℃ and 1.00-3.00 GPa using alkaline basalt as starting material. The compositions of quenched basaltic glasses in the products were detected by electron micro probe. Their CIPW norms were calculated and their refractive indices were determined by the oil-infused method. The Raman spectrum of the quenched basaltic glasses indicates that their main structural species are monomer [SiO4]4-, chain [Si2O6]4- and sheet [Si2O5]2- . The relationship at the same temperature between the proportions of integrated areas of structural species, and compositions and pressures was discussed.     

电弧增材熔池流动特性及稳定性数值模拟

为探究熔池热状态及流动特征对熔池尺寸及其稳定性的影响,本文利用FLUENT软件及二次开发建立电弧增材熔池三维数值模型。数值结果表明了电弧增材是一个快热急冷的熔池非平衡凝固过程,电弧力及马兰戈尼效应对熔池流动影响较大,且熔池内部流态以环流为主。综合分析了热输入及热耗散对熔池局域温度场及流场的影响,熔池热状态通过影响熔体粘度、各驱动力而改变熔池流态及流速,而熔池流动则影响熔池边界及热对流,因此二者的综合作用决定了熔池几何。而层间冷却能够改善沉积时熔池热耗散条件,减小热积累的影响,但会降低成形效率。     

几种纯金属熔体原子团簇的微观热收缩现象

利用高温液态金属X射线衍射仪对纯金属In、Ga、Ge、Ag、Cu、Al、Sn等在液相线以上不同温度进行了实验研究,得到了其衍射强度、结构因子、双体分布函数、径向分布函数以及平均最近邻原子间距、原子配位数.实验结果表明,纯金属In、Ge、Ag、Cu、Al、Sn等在液相线以上较大温度范围内,原子团簇都存在微观热收缩现象,几种金属的微观热收缩都具有一个共同的特点--在整个测试温度区间内热收缩是不均匀的,每种金属在各温度区间内的热收缩程度以及特征不同.在此基础上进一步探讨了微观热收缩现象的机理以及熔体内发生的结构变化.     

氧气底吹造锍过程中气泡行为的水模实验

通过底吹炼铜转炉水模型实验,研究底吹造锍转炉中喷嘴数量、喷嘴角度、喷嘴直径、气流速度等因素对转炉熔池气泡大小、气含率及液面喷溅的影响规律.结果表明:喷嘴直径的增大不利于气泡微细化,且加剧了液面喷溅现象;喷嘴角度的增大有利于减小喷溅,但气含率下降;气流速度的增大有利于气泡微细化,显著提高气含率,但喷溅比较剧烈.与单喷嘴喷吹相比,在总喷气量相同的条件下,双喷嘴喷吹具有明显的优势,两种方法的气泡微细化程度差别不大,但是双喷嘴的喷溅情况明显减弱;双喷嘴夹角44°时能获得最大的气含率,约为9%.     

氯化物熔体中镨钴合金形成的电化学研究

用循环伏安法，恒电位电解断电后的电极电位－时间曲线研究了Ｐｒ（Ⅲ）在ＮａＣｌ－ＫＣｌ－ＰｒＣｌ３熔体中，钴电极上还原的电极过程，首先生成Ｐｒ２Ｃｏ１７，随后依次形成含Ｐｒ量较多的Ｐｒ－Ｃｏ金属间化合物，然后才析出纯金属镨；验证了在１０７３Ｋ形成Ｐｒ－Ｃｏ合金的数目．测得Ｐｒ２Ｃｏ１７，ＰｒＣｏ５，Ｐｒ５Ｃｏ１９和Ｐｒ２Ｃｏ７在１０７３Ｋ的标准生成自由能分别为－１５６．３３，－４９．２２，－１８８．１８，－３４．７４ｋＪ·ｍｏｌ－１．并发现在ＮａＣｌ－ＫＣｌ－ＰｒＣｌ３－ＣｏＣｌ２熔体中，Ｐｒ（Ⅲ）和Ｃｏ（Ⅱ）在钼电极上可发生共沉积     

Al-Zr(CO3)2-KBF4反应合成复合材料的制备与性能

采用熔体反应法，以Al-Zr(CO3)2-KBF4反应体系原位反应合成颗粒增强铝基复合材料。用SEM分析生成的复合材料微观组织，用水淬快速冷却得到的增强相颗粒，尺寸细小并且在基体中分布均匀.XRD分析表明：Zr(CO3)2和KBF4与铝液反应生成ZrB2、Al2O3、ZrAl3颗粒，金属型复合材料的增强相颗粒尺寸显著增大，复合材料的拉伸强度和显微硬度随加入的反应物质量分数的增加而增大，但是延伸率先升后降，属塑性断裂。     

底吹氩钢包内三维流场的数值模拟

利用商业Phoenics软件对某钢厂230 t 钢包底吹氩精炼钢包内钢液的流场进行数值模拟计算,并从流场分布和湍动能分布等角度分析了不同喷嘴布置和不同吹气量对钢包内钢液混匀效果的影响.结果表明,底吹氩钢包内透气元件采用0.6R-β布置可避免钢液对包壁所造成的严重冲刷,且有利于减少钢包内钢液的混匀时间,从而获得较为理想的搅拌效果.