科创中国

Influence of geometric and cutting parameters of cemented carbide cutting tool on reliability of cutting tool has become more and more mature,yet influence of its physical and material parameters on reliability is still blank.In view of this,cutting test and fatigue crack growth test of YT05 cemented carbide cutting tool are conducted to measure such data as the original crack size,growth size,times of impact loading,number and time of cutting tool in failure,and stress distribution of cutting tool is also obtained by simulating cutting process of tools.Mathematical models on dynamic reliability and dynamic reliability sensitivity of cutting tool are derived respectively by taking machining time and times of impact loading into account,thus change rules of dynamic reliability sensitivity to physical and material parameters can be obtained.Theoretical and experimental results show that sensitive degree on each parameter of tools increases gradually with the increase of machining time and times of impact loading,especially for parameters such as fracture toughness,shape parameter,and cutting stress.This proposed model solves such problems as how to determine the most sensitive parameter and influence degree of physical parameters and material parameters to reliability,which is sensitivity,and can provide theoretical foundation for improving reliability of cutting tool system.

Blade vibration failure is one of the main failure modes of compressor wheel of turbocharger for vehicle application.The existing models for evaluating the reliability of blade vibration of compressor wheel are static,and can not reflect the relationship between the reliability of compressor wheel with blade vibration failure mode and the life parameter.For the blade vibration failure mode of compressor wheel of turbocharger,the reliability evaluation method is studied.Taking a compressor wheel of turbocharger for vehicle application as an example,the blade vibration characteristics and how they change with the operating parameters of turbocharger are analyzed.The failure criterion for blade vibration mode of compressor wheel is built with the Campbell diagram,and taking the effect of the dispersity of blade natural vibration frequency and randomness of turbocharger operating speed into account,time-dependent reliability models of compressor wheel with blade vibration failure mode are derived,which embody the parameters of blade natural vibration frequency,turbocharger operating speed,the blade number of compressor wheel,life index and minimum number of resonance,etc.Finally,the rule governing the reliability and failure rate of compressor wheel and the method for determining the reliable life of compressor with blade vibration is presented.A method is proposed to evaluate the reliability of compressor wheel with blade vibration failure mode time-dependently.

A root hinge drive assembly is preferred in place of the classical viscous damper in a large solar array system.It has advantages including better deployment control and higher reliability.But the traditional single degree of freedom model should be improved.A multiple degrees of freedom dynamics model is presented for the solar arrays deployment to guide the drive assembly design.The established model includes the functions of the torsion springs,the synchronization mechanism and the lock-up impact.A numerical computation method is proposed to solve the dynamics coupling problem.Then considering the drive torque requirement calculated by the proposed model,a root hinge drive assembly is developed based on the reliability engineering design methods,and dual actuators are used as a redundancy design.Pseudo-efficiency is introduced and the major factors influencing the(pseudo-)efficiency of the gear mechanism designed with high reduction ratio are studied for further test data analysis.A ground prototype deployment test is conducted to verify the capacity of the drive assembly.The test device consists of a large-area solar array system and a root hinge drive assembly.The RHDA development time is about 43 s.The theoretical drive torque is compared with the test values which are obtained according to the current data and the reduction efficiency analysis,and the results show that the presented model and the calibration methods are proper enough.

目的 修订中文版亲密关系冲突应对方式量表并检验其在中国群体中的信效度.方法 通过翻译和回译以及专家评审和预实验的方法形成原始的中文量表,对223名中国已婚被试进行测量,完成量表的条目筛选和探索性因素分析,确定正式的中文量表.然后在454名中国已婚被试中施测以检验中文量表的信效度.对其中78名被试在1个月后再次施测,考察重测信度.结果 探索性因素分析表明,中文版亲密关系冲突应对方式量表由7个因子构成,可解释的总变异率为60.887%,与原版量表的6因子结构存在差异.经过验证性因素分析发现中文量表的6因子模型比7因子模型拟合的更好,并结合专家意见最终确定中文版量表包含妥协、控制、顺从、分离、回避和行为反应共6个因子,30个条目.各因子 x的Cronbach'sα系数、分半信度系数和重测信度系数分别为0.604~0.872、0.613 ~0.808、0.611 ~0.672,均达到统计学意义.结论 中文版亲密关系冲突应对方式量表具有较好的信、效度,可以用于评估中国夫妻的冲突应对行为.