.246 北京科技大学学报 第29卷 Prediction of glass forming ability using atomic radius and electro negativity JI Xiulin),CAI Anhui2),PAN Ye) 1)Materials Science and Engineering School.Southeast University,Nanjing 210096,China 2)Hunan Institute of Science and Technology.Yueyang 414006.China ABSTRACI A method based on atomic radius and electro-negativity of alloying constituents was proposed to estimate the glass forming ability(GFA)of a bulk metallic glass.The mathematical model of the ratio of radius- es difference to electro-negativity difference and the critical cooling rate Rc was established.The same relation- ships with a shape of upturned parabola in all five kinds of alloys were obtained with this model.Based on the above results,four different compositions of ZrAl-Ni Cu bulk metallic glasses were designed and prepared, and their critical size Zm,super-cooling liquid region ATx and the reduced glass temperature Trg were all mea- sured respectively.The results show that the glass forming ability of Zrs4Al13NiisCuis is the best in the four al- loys and the GFA order of these alloys predicted using the d/Ae model is basically consistent with experimental parameters (includingTs and T).It is concluded that the prediction using the d/Ae model is a reli- able method to compare the glass forming ability between different compositions in a same alloying series. KEY WORDS metallic glass:glass forming ability;design of compositions;radius;electro-negativity (上接第231页) Plain group analysis of 2D braided composites geometry MA Wensuo）,FENG Wei) 1)Mechatronics Engineering School.Henan University of Science and Technology.Luoyang 471003.China 2)Shanghai Institute of Applied Mathematics and Mechanics,Shanghai University,Shanghai 200071,China ABSTRACI Seventeen plain groups,which were associated with 2D braided geometry of composites,were de- duced from the combination of ten plain point groups and five plain dot lattices.The simplified method,combi- nation and crossover principle of the point symbol on a 2D braided composites yarn segment were proposed.The construction methods of non-symmetry unit and basic symmetry unit were investigated,and the fabric-braided procedure from nonsymmetry unit to basic symmetry unit was discussed.The 2D braided fabric of composites was classified four braided families,each braided family included several plain groups,each plain group was cor- responding a group of braided structures,and each group of braided structures had one or several braided modes whose interwoven methods were homologous.The possible 2D braided composites geometry of majority plain groups was illustrated. KEY WORDS braided composite;braided geometry:analysis of group theory;point group;plain groupPrediction of glass forming ability using atomic radius and electro-negativity JI Xiulin 1）‚CAI A nhui 2）‚PA N Ye 1） 1） Materials Science and Engineering School‚Southeast University‚Nanjing210096‚China 2） Hunan Institute of Science and Technology‚Yueyang414006‚China ABSTRACT A method based on atomic radius and electro-negativity of alloying constituents was proposed to estimate the glass forming ability （GFA） of a bulk metallic glass．The mathematical model of the ratio of radius￾es difference to electro-negativity difference and the critical cooling rate Rc was established．The same relation￾ships with a shape of upturned parabola in all five kinds of alloys were obtained with this model．Based on the above results‚four different compositions of Zr—Al—Ni—Cu bulk metallic glasses were designed and prepared‚ and their critical size Zmax‚super-cooling liquid region ΔTx and the reduced glass temperature Trg were all mea￾sured respectively．The results show that the glass forming ability of Zr54Al13Ni15Cu18is the best in the four al￾loys and the GFA order of these alloys predicted using theΔd／Δe model is basically consistent with experimental parameters （including Zmax‚ΔTx‚and Trg）．It is concluded that the prediction using theΔd／Δe model is a reli￾able method to compare the glass forming ability between different compositions in a same alloying series． KEY WORDS metallic glass；glass forming ability；design of compositions；radius；electro-negativity （上接第231页） Plain group analysis of 2D braided composites geometry MA Wensuo 1）‚FENG Wei 2） 1） Mechatronics Engineering School‚Henan University of Science and Technology‚Luoyang471003‚China 2） Shanghai Institute of Applied Mathematics and Mechanics‚Shanghai University‚Shanghai200071‚China ABSTRACT Seventeen plain groups‚which were associated with2D braided geometry of composites‚were de￾duced from the combination of ten plain point groups and five plain dot lattices．The simplified method‚combi￾nation and crossover principle of the point symbol on a2D braided composites yarn segment were proposed．The construction methods of non-symmetry unit and basic symmetry unit were investigated‚and the fabric-braided procedure from non-symmetry unit to basic symmetry unit was discussed．The2D braided fabric of composites was classified four braided families‚each braided family included several plain groups‚each plain group was cor￾responding a group of braided structures‚and each group of braided structures had one or several braided modes whose interwoven methods were homologous．The possible 2D braided composites geometry of majority plain groups was illustrated． KEY WORDS braided composite；braided geometry；analysis of group theory；point group；plain group ·246· 北 京 科 技 大 学 学 报 第29卷