In order to minimize the crystal phase in Al-Cu-Ti amorphous powder,Al65Cu35-xTix amorphous powders were optimized via ball milling through adjusting the amount of Cu and Ti elements and the ball milling time.The resu...In order to minimize the crystal phase in Al-Cu-Ti amorphous powder,Al65Cu35-xTix amorphous powders were optimized via ball milling through adjusting the amount of Cu and Ti elements and the ball milling time.The results show that increasing the mole fraction of Ti can decrease the amount of Al Cu2Ti,Cu9Al4,and Al2Cu intermetallics formed during the process of ball milling;and prolonging the ball milling time can reduce the element crystalline phase to almost none.The optimal composition is determined to be Al65Cu16.5Ti18.5.TiH2 forms in all selected Al65Cu35-xTix amorphous powders during the process of optimization.H atom is decomposed from toluene and reacts with Ti during ball milling,leading to the formation of TiH2.The volume fraction of TiH2 in Al65Cu16.5Ti18.5 amorphous powder is measured to be 4.30%.展开更多
Irregular plates are very common structures in engineering,such as ore structures in mining.In this work,the Galerkin solution to the problem of a Kirchhoff plate lying on the Winkler foundation with two edges simply ...Irregular plates are very common structures in engineering,such as ore structures in mining.In this work,the Galerkin solution to the problem of a Kirchhoff plate lying on the Winkler foundation with two edges simply supported and the other two clamped supported is derived.Coordinate transformation technique is used during the solving process so that the solution is suitable to irregular shaped plates.The mechanical model and the solution proposed are then used to model the crown pillars between two adjacent levels in Sanshandao gold mine,which uses backfill method for mining operation.After that,an objective function,which takes security,economic profits and filling effect into consideration,is built to evaluate design proposals.Thickness optimizations for crown pillars are finally conducted in both conditions that the vertical stiffness of the foundation is known and unknown.The procedure presented in the work provides the guidance in thickness designing of complex shaped crown pillars and the preparation of backfill materials,thus to achieve the best balance between security and profits.展开更多
Metal matrix composites reinforced with graphite particles provide better machinability and tribological properties. The present study attempts to find the optimal level of machining parameters for multi-performance c...Metal matrix composites reinforced with graphite particles provide better machinability and tribological properties. The present study attempts to find the optimal level of machining parameters for multi-performance characteristics in turning of Al-SiC-Gr hybrid composites using grey-fuzzy algorithm. The hybrid composites with 5%, 7.5% and 10% combined equal mass fraction of SiC-Gr particles were used for the study and their corresponding tensile strength values are 170, 210, 204 MPa respectively. Al-10%（SiC-Gr） hybrid composite provides better machinability when compared with composites with 5% and 7.5% of SiC-Gr. Grey-fuzzy logic approach offers improved grey-fuzzy reasoning grade and has less uncertainties in the output when compared with grey relational technique. The confirmatory test reveals an increase in grey-fuzzy reasoning grade from 0.619 to 0.891, which substantiates the improvement in multi-performance characteristics at the optimal level of process parameters setting.展开更多
supported by the Taishan Scholar Construction Engineering by Shandong Government the National Natural Science Foundation of China under Grant Nos.61120106011 and 61203029
基金Projects(51271036,51471035,51101018)supported by the National Natural Science Foundation of ChinaProject supported by the Program of"One Hundred Talented People"of the Chinese Academy of Sciences
文摘In order to minimize the crystal phase in Al-Cu-Ti amorphous powder,Al65Cu35-xTix amorphous powders were optimized via ball milling through adjusting the amount of Cu and Ti elements and the ball milling time.The results show that increasing the mole fraction of Ti can decrease the amount of Al Cu2Ti,Cu9Al4,and Al2Cu intermetallics formed during the process of ball milling;and prolonging the ball milling time can reduce the element crystalline phase to almost none.The optimal composition is determined to be Al65Cu16.5Ti18.5.TiH2 forms in all selected Al65Cu35-xTix amorphous powders during the process of optimization.H atom is decomposed from toluene and reacts with Ti during ball milling,leading to the formation of TiH2.The volume fraction of TiH2 in Al65Cu16.5Ti18.5 amorphous powder is measured to be 4.30%.
基金Project (51504044) supported by the National Natural Science Foundation of ChinaProject (14KF05) supported by the Research Fund of the State Key Laboratory of Coal Resources and Mine Safety(CUMT),China+2 种基金Project (2015CDJXY) supported by the Fundamental Research Funds for the Central Universities,ChinaProject (2015M570607) supported by Postdoctoral Science FoundationProject (2011DA105287-MS201503) supported by the Independent Subject of State Key Laboratory of Coal Mine Disaster Dynamics and Control,China
文摘Irregular plates are very common structures in engineering,such as ore structures in mining.In this work,the Galerkin solution to the problem of a Kirchhoff plate lying on the Winkler foundation with two edges simply supported and the other two clamped supported is derived.Coordinate transformation technique is used during the solving process so that the solution is suitable to irregular shaped plates.The mechanical model and the solution proposed are then used to model the crown pillars between two adjacent levels in Sanshandao gold mine,which uses backfill method for mining operation.After that,an objective function,which takes security,economic profits and filling effect into consideration,is built to evaluate design proposals.Thickness optimizations for crown pillars are finally conducted in both conditions that the vertical stiffness of the foundation is known and unknown.The procedure presented in the work provides the guidance in thickness designing of complex shaped crown pillars and the preparation of backfill materials,thus to achieve the best balance between security and profits.
文摘Metal matrix composites reinforced with graphite particles provide better machinability and tribological properties. The present study attempts to find the optimal level of machining parameters for multi-performance characteristics in turning of Al-SiC-Gr hybrid composites using grey-fuzzy algorithm. The hybrid composites with 5%, 7.5% and 10% combined equal mass fraction of SiC-Gr particles were used for the study and their corresponding tensile strength values are 170, 210, 204 MPa respectively. Al-10%（SiC-Gr） hybrid composite provides better machinability when compared with composites with 5% and 7.5% of SiC-Gr. Grey-fuzzy logic approach offers improved grey-fuzzy reasoning grade and has less uncertainties in the output when compared with grey relational technique. The confirmatory test reveals an increase in grey-fuzzy reasoning grade from 0.619 to 0.891, which substantiates the improvement in multi-performance characteristics at the optimal level of process parameters setting.
基金supported by the National Natural Science Foundation of China under Grant Nos.71125005,70871108,and 70810107020Outstanding Talents Funds of Organization Department,Beijing Committee of CPC
文摘supported by the Taishan Scholar Construction Engineering by Shandong Government the National Natural Science Foundation of China under Grant Nos.61120106011 and 61203029
