| 1. | It is indicated that three - roll cross wedge rolling process has a distinct advantage in the forming quality of the center of rolled pieces 分析表明,三辊楔横轧轧制工艺在轧件心部成形质量上具有明显的优势。 |
| 2. | In this region of a recent fracture , callus is seen forming at the broken ends of bony trabeculae that extend to the center from the left and top 在新骨折区域可见骨小梁破损端有从中心部延至左侧和顶部的的骨痂形成。 |
| 3. | The ratio of v - anvil width in the fmv forging method is optimized with numerical simulation according to the principle of larger deformation in the ingot center and smaller load 按照工件心部变形大、载荷小的原则,得到的优化结果是:上下砧宽比= 1 : 1 . 5时压实效果最好。 |
| 4. | The following adverse reactions may occasionally occur : dryness of the mouth , thirst , drowsiness , fatigue , dizziness , heartburn , anorexia , abdominal discomfort and exanthema 偶尔可能出现下列副作用:口干、口渴、发困、乏力、头晕、心部烧灼感、食欲不振、腹部不适、药疹。 |
| 5. | The results indicate that the surface grain size of the steel sheets is smaller than that of the center by batch annealing , while it is on the contrary of the steel sheets by continuous annealing 结果表明,罩式退火后钢板表面晶粒比心部的细小,而连续退火后钢板表面晶粒比心部的粗。 |
| 6. | The difference is mainly resulted from the original structure and texture inhomogeneity of hot rolled steel plates , and the process of heating and annealing can also have a great effect on the inhomogeneity of the surface and center grain sizes in the steel sheets 这种区别主要来源于热轧钢板原有组织和织构的不均匀性,退火加热过程也会对钢板表面和心部晶粒尺寸的不均匀性产生很大影响。 |
| 7. | Abstract : by utlizing abundant local resource of ytirium and combining the characteristics of magnesium , barium , calcium and silicon , a sort of composite nodulizer - ytirium - based heavy rare earth nodulizer was developed which is characterized by its good desulphurizing and deoxidizing rate effect , excellent effect to neutralize anti - nodulizing effect of trace elements , strong nodulizng effect and degeneration - resistance , good effect to fine matrix structure , decreased chilling tendency and wide scope of applicatiom using this nodulizer to produce some important castings such as water - cooled wall of blast furnace and roller could increase mechanical properties of central area and casting yield 文摘:利用江西省丰富的钇基重稀土,结合镁、钡、硅、钙等元素的特性开发了钇基重稀土复合球化剂,该球化剂具有脱硫、脱氧、抗干扰元素、球化和抗球化衰退能力强,细化基体组织,白口倾向小,适用范围宽等特点,应用于高炉冷却壁,轧辊等关键铸件上可提高心部力学性能和工艺出品率。 |
| 8. | Presents the investigation of the heat conduction behavior , internal thermal stress field of specimen under thermal shock and microscopic damage and failure of the tungsten based composites by combination of macroscopic and microscopic analyses and integration of material science and mechanics ; describes a microscopic mechanical model based on the microstructure of components with macroscopic stress applied to the microscopic model as that of maximum principal stress at the center , and the fringe of the specimen , and the microscopic stress fields obtained through calculation by the finite element method , and concludes from test results that the maximum principal stress is first generated inside the test coupon , , and a failure will be first initiated in the inclusion if the material fails at this time ; the maximum principal stress moves to the edge of the test coupon after the test coupon is heated for a period of time , and the failure will first be initiated in the base if the material fails at this time 从材料设计的思想出发,采用宏观与微观、材料科学与力学相结合的方法,对钨基复合材料的热传导行为、材料在热冲击载荷下的内部热应力场及材料细观结构的破坏行为进行了详细的理论研究.根据钨基复合材料的细观组织结构建立了材料细观模型.在宏观分析的基础上,分析了材料微结构内部的破坏行为.分别取试件心部与边缘主应力值最大点的应力状态,施加在所建立的模型上,用有限元方法计算了模型内部的弹性应力场.结果表明:试件主应力最大值首先产生在试件内部,此时,如果材料发生破坏将先从夹杂中开始;加热一段时间后试件中的最大主应力值转移到试件边缘,此时材料发生破坏将先从基体中开始 |
| 9. | The temperature field of the huge stream turbine rotor during free forging is numerically simulated with different process parameters . the purpose is to find out a set of optimum process parameters so that the temperature of the rotor center does not exceed the limit temperature of abnormal grain growth which is about 1100c 对大型汽轮机转子锻造过程中的成形火次进行了温度场的数值模拟和优化,得到了控制转子锻件心部温度不超过1100的工艺参数,为实际生产解决混晶问题提供了参考数据。 |
| 10. | Considering different microstructures and properties of metal of hardened layer and the core of back - up roller , the distributions of shear stress below surface and the contact stress between work roller and back - up roller of a four - high - mill were simulated with nonlinear fem 摘要考虑轧辊表面淬硬层与其心部金属材料组织性能的差别,采用非线性有限元方法对四辊轧机的工作辊与支撑辊间接触应力及辊内剪应力分布进行模拟,并将模拟结果与传统强度校核方法进行了对比分析,研究了轧辊淬硬层厚度对辊间接触应力的影响规律。 |