Microstructure Control and Creep Strength of Particle Reinfored Aluminum Composites.

颗粒增强铝复合材料的微观结构控制和蠕变强度。

• 批准号: 61550521
• 负责人: MATSUURA Keisuke
• 金额: $ 1.34万
• 依托单位: YAMAGATA University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-61550521/
• 关键词: Dispersion-Hardening; Short Fibre-Reinforcement; Mechanical Alloying; Creep; -Projection; θプロジェクション; クリープ変形; 限界応力Al基複合材; 組織制御

CREEP TESTS WERE CARRIED OUT ON SOME DISPERSION-HARDENED Al-Al_4 C_3 SYSTEM ALLOYS AND SHORT FIBRA-REINFORCED Al-Al_2 O_3YLLOYS TO EXAMINE THE CREEP BEHAVIOR AND THE EFFECT OF HEAT TREATMENT ON IT. MAIN RESULTS ARE AS FOLLOWS:1. Al-Al_4 C_3-4%Mg ALLOY(4.5 VOL.% DISPERSOIDS) AND Al-Al_4 C_3ALLOY(9 VOL.% DISPERSOIDS).(1) THE MICROSTRUCTURE OF THESE ALLOYS CONSISTED OF VERY FINE SUBGRAINS OF ABOUT 0.4-0.8 <micrn>m WHICH WERE STABLE UP TO ABOUT 873K. AS THE ANNEALING TIME AT 823 K INCREASED FROM1h TO 24 h, THE SIZES OF SUBGRAINS AND DISPERSOIDS CHANGED ONLY BY ABOUT 20%, WHILE THE CREEP STRENGTH WAS APPRECIABLY DECREASED BY THE INCREASE OF ANNEALING TIME.(2) CREEP CURVE SHAPE AND MINIMUM CREEP RATE WERE DRASTICALLY CHANGED WITH STRESS NEAR A CRITICAL STRESS. THE CREEP CURVE WAS MAINLY DOMINATED BY THE PRIMARY AND SECONDARY STAGES IN THE STRESS RANGE BELOW THE CRITICAL STRESS AND BY THE TERTIARY STAGE IN THE STRESS RANGE ABOVE IT.(3) THE DECREASE OF CREEP STRENGTH BY INCREASE OF ANNEALING T … More IME WAS CAUSED FROM DECREASE OF THE CRITICAL STRESS, POSSIBLY DUE TO THE CHANGE OF DISLOCATION STRUCTURE IN SUB-BOUNDARIES. ON THE OTHER HAND, THE CRITICAL STRSS WAS ENHANCED BY PREVIOUS CREEP DEFORMATION AT STRESSES LOWER THAN THE CRITICAL STRESS, POSSIBLY DUE TO THE STRENGTHENING OF SUB-BOUNDARIES.2. SHORT FIBRE-REINFORCED Al-Al_2O_3 ALLOYS(VOLUME FRACTION: 5, 10 AND 18%).(1) THE ALLOYS WERE ANNEALED 2 h at 773 K. THE CREEP CURVE MAINLY CONSISTED OF THE TERTIARY STAGE IN THE LOW STRESS RANGE WHEARE THE INSTANTAMEOUS STRAIN WAS ONLY ELASTIC, WHILE THE PRIMARY STAGE WAS DOMINANT IN THE HIGH STRESS RANGE WHERE THE INSTANTANEOUS STRAIN HAD THE PLASTIC COMPONENT.(2) <theta>-PROJECTION CONCEPT WAS SUCCESSFULLY APPLIED TO THE ANALYSIS OF CREEP CURVES. THE <theta>PARAMETERS PRESENTING THE RATE CONSTANTS OF PRIMARY AND TERTIARY CREEPS RESPECTIVELY, <theta>_2 AND<THETA>_4 WERE ABOUT EQUAL AND DETERMINED BY THE SELF DIFFUSION OF ALUMINUM.(3) THE CREEP CURVE OR CREEP RATE WERE NOT AFFECTED BY THE VOLUME FRACTION OF FIBRES WHEN IT WAS LARGER THAN 10%. Less

本文对弥散强化的Al-Al_4C_3系合金和短纤维增强的Al-Al_2O_3基合金进行了蠕变试验，以研究其蠕变行为及热处理对其的影响。Al-Al_4C_3 -4%Mg合金（体积分数4.5%）Al-Al_4C_3合金（体积分数为9%）分散体）。(1)这些合金的显微组织是由0.4-0.8 μ m的非常细小的亚晶<micrn>组成，在873 K左右是稳定的。在823 K下退火时间从1 h增加到24 h，亚晶和弥散体尺寸变化不大，约为20%，而蠕变强度随退火时间的增加而显著降低。(2)在临界应力附近，蠕变曲线形状和最小蠕变速率随应力变化剧烈。在临界应力以下的应力范围内，蠕变曲线主要受第一、第二阶段的控制，在临界应力以上的应力范围内，蠕变曲线主要受第三阶段的控制。(3)提高退火温度对蠕变强度的影响 ...更多信息 IME的产生是由于亚晶界位错结构的变化引起的临界应力的降低。另一方面，在低于临界应力的应力下，蠕变变形使临界应力增大，这可能是由于亚边界的强化。短纤维增强Al-Al_2 O_3合金（体积分数：5，10，18%）(1)合金在773 K退火2 h。蠕变曲线在低应力区主要由第三阶段组成，此时应变仅为弹性，而在高应力区主要由第一阶段组成，此时应变具有塑性成分。(2)将<theta>投影概念成功地应用于蠕变曲线的分析。表示<theta>一次蠕变和三次蠕变速率常数的<theta>参数_2和<THETA>_4大致相等，并受铝的自膨胀影响。(3)当纤维体积分数大于10%时，蠕变曲线或蠕变速率不受纤维体积分数的影响。少

项目成果

K.Matsuura: Proc.of Sintering´87,11SS. (1988)

K.Matsuura：Proc.of Sintering´87,11SS (1988)

K. Matsuura: "Creep Behaviour of Dispersion-Hardened al-Al_2 O_3 Alloy with Zirconium Addition." Proc. Intern. Conf. on Creep, JSME, IMechE, ASTM, ASME. 199-204 (1986)

K. Matsuura：“添加锆的弥散硬化 al-Al_2 O_3 合金的蠕变行为”。

K.Matsuura: Proc.Int.Conf. on Creep. 199-204 (1896)

K.Matsuura：Proc.Int.Conf。

松浦圭助他: 日本金属学会講演概要. 209-209 (1986)

Keisuke Matsuura 等人：日本金属学会讲座摘要 209-209 (1986)。

N. Matsuda: "Creep Behaviour and Dislocation Structures in Al-Al_2O_3 Alloys." T. Japan Inst. Metals. 28. 392-405 (1987)

N. Matsuda：“Al-Al_2O_3 合金中的蠕变行为和位错结构。”