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. In the process of coarsening and growth, the mechanism of combining growth and Ostwald ripening coexist and together affect morphology and size of the solid phase particles. The optimum process...熔化,合金中的大块状组织逐渐演变为球状组织;但是,保温温度过高或保温时间过长,都会引起球状颗粒的粗化长大.在粗化长大过程中,合并长大机制和Ostwald熟化机制同时存在,共同影响固相颗粒的形貌和尺寸大小.ZC61-0.3Cr镁合金半固态成形所需的最佳工艺条件为(585 ℃, 30 min);此条件下,其颗粒平均尺寸,形状因子和固相率分别为43 μm,1.4和51%. 关键词:ZC61-0.3Cr镁......
the separation of the structure. The different curvature of the grain surface makes the grain spheroidize. The main mechanism of the merger roughening stage is merger growth and Ostwald ripening. Key words...因子和颗粒平均尺寸分别为65% ,1.37及45 μm.增加等温温度或延长保温时间均使得半固态组织颗粒平均尺寸和形状因子先减小后增大,固相率则一直下降.合金在重熔过程中发生相的转变,主要有枝晶快速粗化合并,组织分离,球化,晶粒合并粗化等状态.亚晶界提供溶质原子扩散通道,枝晶根部优先熔断,从而促进组织分离,晶粒表面曲率不同使得晶粒球化,合并粗化阶段主要机制为合并长大以及Ostwald熟化. 关键词......
of microstructure. Besides, average particle size constantly increases with prolonging the holding time because that Ostwald ripening can improve the degree of spheroidization. The current coarsening...拌电流及搅拌频率的增大,半固态 2A50合金的显微组织由树枝晶转变为越来越细小均匀的近球状晶,且二次重熔后的球状晶粒也越来越圆整.搅拌参数为30 A和30 Hz时,二次重熔后的半固态2A50合金的球状晶粒平均尺寸约为80 μm,形状因子约为0.76,进一步增加搅拌电流或者搅拌频率,显微组织没有明显的改善.二次重熔过程中半固态2A50合金平均晶粒尺寸随着保温时间的延长而逐渐增大,Ostwald粗化机......
evolution includes the agglomeration of α-phase and Ostwald ripening. Precipitations prepared by solution and aging treatment prevent the grains from coarsening and promote the grain ripening to globular... this Ostwald ripening progress, the curvature of different interface eventually goes uniform, and the solid grains become globular. This conclusion of two-stage microstructure evolution is supported by LU......
the Ostwald ripening mechanism, and adding Al element into Mg-7Zn alloy results in a decrease of coarsening rate of solid particles in semi-solid slurry, consequently, it can obtain the perfect semi...渐降低,而在后期处于固液平衡阶段,固相率的变化不明显;同时,固相颗粒粗化符合Ostwald熟化机制,且Al元素的加入减小了初生固相颗粒的粗化速率,从而在较宽的保温时间范围内可获得细小圆整的固相颗粒. 关键词:Al含量;Mg-Zn-Al合金;半固态;粗化 中图法分类号:TG 146.22  ......
+,Eu3+ shell via the classical Ostwald ripening mechanism. The as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence, which was further made into environmentally benign... to decrease their surface energy, known as the Ostwald ripening phenomenon. In the other aspect, the PAA polymer on the prismatic planes ({1010} crystal planes) was more than that on the top/bottom......
, the coarsening processes of solid grains of as-received and 3P samples were dominated by the coalescence and Ostwald ripening mechanism, respectively. The difference of coarsening processes was mainly... to Ostwald ripening mechanism, which was beneficial to forming of liquid phase among solid particles. When the number of ECAP passes increased continuously to four, the uniformity of liquid film......
be described by Ostwald ripening law. The average grain size increases firstly, subsequently decreases and the shape factor of grains approaches to 1 as the reheating temperature increases... by Ostwald ripening law (D3∝Kt)[10]. Fig.6 Reheating microstructures of billets extruded by ECAE for various holding time Table 5 Average diameter and shape factor of material......
. It was also found that halides can accelerate the speed of Ostwald ripening by adding Cl-, Br- and I-into the aqueous and have some effects on the morphology of the nanoplates. Key words: silver... will transfer from one facet to another and ions in the solution can also produce oxidation etching to form the most stable nanodisks. This phenomenon is called Ostwald ripening [36]. In this experiment......
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