共搜索到67条信息，每页显示10条信息，共7页。用时：0小时0分3秒796毫秒
alloys leans mainly upon the volume fraction and radius of the second phase [2,3]. For Al-Cu-Mg alloys in the α+S phase field, the precipitation sequence is as follows [4,5]: SSS→GPB/co-clusters→GPB2/S...-Mg alloys [J]. Materials Science and Engineering A, 2004, 386(1-2):156-163. [17] KOVARIK L, COYRT S A,FRASER H L, MILLS M J. GPB zones and composite GPB/GPBII zones in Al-Cu-Mg alloys [J]. Acta......
elongated along the [100]Al direction [15]; the general precipitation sequence during the aging is represented as [16,17]: supersaturated solid solution (SSSS) → Cu-Mg co-clusters (GPB zone) → S″/S′ → S......
-B区形成来决定的.Wang等[40]通过采用TEM和DSC手段研究了Al-2.81Cu-1.05Mg-0.41Mn合金溶质原子的析出行为,认为S相是峰值时效的主要强化相,而S″相主要出现在第一阶段强化的后期. 在不考虑具体强化阶段的情况下,可以认为S相的析出序?为:SSSα→Cu-Mg原子团聚集区(cluster)或GPB Zones→S″(圆柱状,共格)→S′相→S相. 3.3 ... alloy[J]. Acta Materialia, 2001, 49(5): 913-920. [34] Charai A, Walther T, Alfonso C, Zahra A M, Zahra C Y. Coexistence of clusters, GPB zones, S″-, S′- and S-phases in an Al-0.9%Cu-1.4%Mg alloy[J]. Acta......
硬度随时效时间的延长而增大,在12 h就达到峰值(161.5 HV),然后逐渐下降.应力时效的硬度在16 h达到峰值(157.9 HV),在1~16 h时,硬度出现一个缓慢上升的过程,这是GP区(或GPB区)形成所致.与普通时效相比,应力时效的欠时效过程明显延长,硬化速率缓慢.表明时效过程中外加应力显著降低合金的时效硬化能力,并减慢合金的硬化速度.值得注意的是,应力时效的峰值硬度稍低于普通时效的峰......
transformation curves of 7A04 aluminum alloy[J]. The Chinese Journal of Nonferrous Metals, 2010, 20(4): 640-646. [12] KOVARIK L, COURT S A, FRASER H L, MILLS M J. GPB zones and composite GPB/GPBII......
时效析出序列可以表示为GP 区(沿α面偏聚)→θ″→θ′→θ,添加Ag的Al-Cu-Mg-Ag合金的析出序列为GPB 区(沿{111}面偏聚)→Ω→θ,相对于θ′相,Ω相具有更优良的抗粗化能力和强化能力[1-2].时效序列的改变是因为Mg和Ag之间具有强烈的相互作用,作为合金元素同时添加时,两者形成原子团簇,使得Mg元素在{111}α面上发生偏聚,Mg原子会在Al基体中形成较大的负畸变区,促进Cu......
; 分析与讨论 2124合金的Cu和Mg质量比约为3.2,属于低Cu和Mg质量比合金,对于此类Al-Cu-Mg系合金,S相的脱溶序列如下[20-21]:SSS(过饱和固溶体)→GPB→S″/GPB2→ S′→S(Al2CuMg).时效初期,GP区内的原子排列是紊乱的,随时效时间的延长,又变成有序的GP区叫S″相,它仍与母相共格,在母相的(100)方向生长,形成圆柱体；最后,S″区的原子又重新排列,形成......
of model The results from TEM observations of the retrogression microstructures are summarized in Fig. 1. The matrix and grain boundary precipitate (GPB) experience Ostwald ripening both......
)→ Cu-Mg(GPB区)→S″/S′→S′/S(Al2CuMg).可见,试样在有外加应力的时效(蠕变时效)时,由于外加载荷的作用在材料内部引入了位错,使得析出相比于无外加应力时效时析出更细小和致密.相比于无预拉伸的试样,预拉伸2%试样内部析出相形貌明显不同:尺寸更细小,分布更致密.这使得合金时效强化效果增强[22-23], 因而预拉伸2%后试样的强度性能明显升高(见图4).随着预拉伸量的继续增加......
that the structural units in the GPB region formed around S phase at higher aging temperature (above 180 °C) and hindered the growth of S phase along the width direction, resulting in the growth of S phase......
