工程材料輕量化,是航空航天工程、汽車(chē)工業(yè)和高速鐵路等領(lǐng)域的核心目標(biāo)之一
鋁基材料具有高比強(qiáng)度、耐腐蝕、高導(dǎo)熱和高導(dǎo)電等優(yōu)點(diǎn),是一種重要的
輕量化材料[1, 2]
但是多數(shù)鋁基材料的組織在高于250℃的溫度下不穩(wěn)定,其強(qiáng)度隨著溫度的升高而急劇降低
因此,運(yùn)行于中高溫區(qū)間的鋁基材料構(gòu)件難以輕量化[3, 4]
目前,關(guān)于耐熱鋁基材料的研究主要是提高
鋁合金基體的耐高溫性能,包括對(duì)傳統(tǒng)鋁合金進(jìn)行改性、用快速凝固等工藝制備彌散強(qiáng)化鋁合金和添加陶瓷等增強(qiáng)相復(fù)合化,但是難以兼顧高溫強(qiáng)度和制備工藝
例如,在傳統(tǒng)的Al-Cu系和Al-Si系鋁合金中添加Ag等微量元素提高其穩(wěn)定性和高溫強(qiáng)度,但是溫度高于300℃其強(qiáng)度仍然急劇惡化[5, 6]
用快速凝固技術(shù)可在鋁基體中生成大量細(xì)小彌散的亞穩(wěn)定相,以Al-Fe-V-Si等彌散強(qiáng)化鋁合金為典型代表,可使其高溫(300℃)強(qiáng)度明顯高于傳統(tǒng)鋁合金[7]
但是,制備加工流程困難和復(fù)雜
進(jìn)行復(fù)合化提高鋁合金的高溫強(qiáng)度,一直是備受關(guān)注的研究方向
添加SiC、B4C、
碳納米管、
石墨烯等增強(qiáng)相,不僅使其室溫強(qiáng)度明顯提高[8~11],高溫強(qiáng)度或蠕變性能也有不同程度的提高
Al2O3與鋁基體的界面相容性優(yōu)異且沒(méi)有任何界面反應(yīng),在基體中的穩(wěn)定性十分優(yōu)異
而原位生成的納米尺度Al2O3,具有很高的高溫強(qiáng)化作用[12]
金屬氧化物如ZrO2、TiO2和CuO等可與Al發(fā)生原位反應(yīng)生成Al2O3,還能形成金屬間化合物如Al3Zr、Al3Ti和Al2Cu[13~15],因此可實(shí)現(xiàn)協(xié)同強(qiáng)化
在鋁合金中添加一定含量的
稀土元素可細(xì)化晶粒,還能與鋁基體生成高熱穩(wěn)定性的金屬間化合物,有利于提高材料的抗蠕變性能[16~19]
因此,向鋁基體中添加稀土金屬氧化物借助原位反應(yīng)同時(shí)生成Al2O3和稀土與鋁的金屬間化合物,有望制備出耐高溫性能更優(yōu)的鋁基
復(fù)合材料
Sakamoto等[20]向鋁基體中添加納米La2O3和Y2O3顆粒,發(fā)現(xiàn)La2O3更易與鋁基體發(fā)生反應(yīng)而生成Al2O3和Al11La3
對(duì)于機(jī)械合金化,Choi等[21]指出,球磨強(qiáng)度主要與球速和球料比有關(guān)
Sakamoto的研究表明,較低的球磨強(qiáng)度和燒結(jié)溫度,不能實(shí)現(xiàn)充分的原位反應(yīng)
鑒于此,本文通過(guò)高能球磨和真空燒結(jié)使鋁與La2O3充分反應(yīng)制備出(Al11La3+Al2O3)/Al復(fù)合材料,并研究其力學(xué)性能和相關(guān)強(qiáng)化機(jī)制
1 實(shí)驗(yàn)方法
實(shí)驗(yàn)用原料是平均直徑為13 μm的工業(yè)純鋁粉(圖1a)和平均尺寸為300 nm的La2O3顆粒(圖1b)
進(jìn)行高能球磨將質(zhì)量分?jǐn)?shù)為8%的La2O3顆粒分散在鋁基體中
為了促進(jìn)鋁與La2O3的反應(yīng),球磨的球料比為15:1,轉(zhuǎn)速為400 r/min,在氬氣保護(hù)下連續(xù)球磨6 h
在粉末中添加2%(質(zhì)量分?jǐn)?shù))的硬脂酸作為過(guò)程控制劑,以避免粉末粘結(jié)成塊
圖1鋁粉、氧化鑭顆粒和球磨粉末的形貌
Fig.1Morphologies of pure Al powders (a), La2O3 particles (b), and mixed powders after HEBM (c)
高能球磨后的混合粉末如圖1c所示
為了確保完全反應(yīng),將混合粉末在630℃熱壓燒結(jié)2 h,燒結(jié)時(shí)真空度為10-1 Pa
最后將燒結(jié)后的坯錠在450℃以16:1的擠壓比制備出復(fù)合材料棒材
為評(píng)價(jià)Al11La3和Al2O3的強(qiáng)化效果,對(duì)純鋁粉進(jìn)行工藝相同的球磨、燒結(jié)和擠壓,制備出對(duì)比樣品
本文所用實(shí)驗(yàn)樣品,均取自熱擠壓棒材
使用X射線衍射儀(X-ray diffraction, XRD)分析復(fù)合材料的物相,用掃描電子顯微鏡(Scanning electron microscopy, SEM, FEI Apreo)和透射電子顯微鏡(Transmission electron microscopy, TEM, FEI Talos)觀察復(fù)合材料的微觀結(jié)構(gòu)
用于TEM觀察的樣品需用5000目砂紙打磨后再用凹坑研磨儀研磨,最后用Gatan PIPS Ⅱ 695精密離子減薄儀將其離子減薄
在平行于擠壓方向加工標(biāo)距尺寸為15 mm×4 mm×2 mm的狗骨形拉伸試樣,使用MTS E45.105萬(wàn)能試驗(yàn)機(jī)分別在室溫和350℃進(jìn)行拉伸實(shí)驗(yàn),應(yīng)變速率為1×10-3 s-1,350℃高溫拉伸的保溫時(shí)間為10 min,每個(gè)材料至少測(cè)試3次
用SEM(FEI Apreo)觀察拉伸斷口
2 實(shí)驗(yàn)結(jié)果和分析2.1 復(fù)合材料的的相組成
圖2給出了高能球磨后的混合粉末和復(fù)合材料的X射線衍射譜
可以看出,在混合粉末的譜中出現(xiàn)了Al11La3衍射峰,表明在高能球磨過(guò)程中發(fā)生了原位反應(yīng)
在復(fù)合材料的譜中出現(xiàn)了顯著的Al11La3衍射峰而沒(méi)有La2O3的衍射峰,表明原位反應(yīng)十分完全
計(jì)算結(jié)果表明,La2O3與Al完全反應(yīng)將得到Al11La3和Al2O3總體積分?jǐn)?shù)為10%的鋁基復(fù)合材料(Al11La3體積分?jǐn)?shù)為8.02%,Al2O3體積分?jǐn)?shù)為1.98%)
圖2高能球磨粉末和復(fù)合材料的X射線衍射譜
Fig.2XRD patterns of mixed powders after HEBM (a) and composite (b)
Sakamoto等[20]用Al-La2O3制備復(fù)合材料時(shí),在球磨過(guò)程中并未發(fā)生原位反應(yīng),燒結(jié)后剩余大量的La2O3
本文實(shí)驗(yàn)中充分的原位反應(yīng),可歸因于球磨和燒結(jié)兩個(gè)過(guò)程
在Sakamoto等[20]使用容積為50 mL的球磨罐,球料比為10:1,轉(zhuǎn)速為700 r/min,球磨100 h,可估算出磨球的平均速度為0.83 m/s;而本文實(shí)驗(yàn)中的罐體容量為5 L,轉(zhuǎn)速為400 r/min,則磨球的平均速度為3.14 m/s
同時(shí),15:1的球料比也使本文實(shí)驗(yàn)中的球磨強(qiáng)度更高,從而球磨6 h便激活了原位反應(yīng)
這表明,為了激活A(yù)l-La2O3原位反應(yīng),球磨強(qiáng)度比球磨時(shí)間更重要,而較高的燒結(jié)溫度則可使反應(yīng)充分
2.2 復(fù)合材料的顯微組織
圖3給出了復(fù)合材料的SEM照片和能譜
從圖3a可見(jiàn),材料中細(xì)小顆粒的分布十分均勻
在較高的放大倍數(shù)下(圖3b)可見(jiàn)這些顆粒的邊緣呈不規(guī)則的鋸齒狀
能譜面掃圖3d,e和能譜分析圖3f表明,這些微米級(jí)顆粒由Al和La元素組成,可推斷其成分為Al11La3
使用截距法和面積法測(cè)量統(tǒng)計(jì)多張SEM圖片中的Al11La3顆粒,可得其平均尺寸為3.2 μm,體積分?jǐn)?shù)為7.94%
這個(gè)結(jié)果,與完全反應(yīng)后的理論值8.02%十分接近,據(jù)此可認(rèn)為L(zhǎng)a2O3的反應(yīng)完全
但是,由于本文的燒結(jié)溫度較高,Al11La3的尺寸較大[20]
使用更高倍數(shù)的SEM可以發(fā)現(xiàn),材料中彌散分布有大量納米級(jí)的針狀相(圖3c),推測(cè)其為另一種反應(yīng)產(chǎn)物Al2O3
圖3復(fù)合材料的低倍和高倍SEM照片、元素面掃和能譜分析
Fig.3SEM images of composite with low (a, b) and high magnifications (c), EDS mapping (d, e) of the same position of (b), and EDS result of position A (f)
圖4給出了復(fù)合材料的TEM照片和對(duì)應(yīng)位置的能譜分析
對(duì)圖4a中微米級(jí)的A相衍射斑點(diǎn)(圖4b)進(jìn)行標(biāo)定,可進(jìn)一步確認(rèn)A相為Al11La3
圖4c~e分別給出了與圖4a相同位置的元素Al、La和O的面掃結(jié)果
可以看出,除了微米級(jí)的Al11La3相,材料中還生成了大量納米級(jí)的針狀A(yù)l2O3,其長(zhǎng)度約為150 nm,寬度約為10 nm
生成納米尺寸Al2O3的主要原因:首先,原料中的La2O3即為納米尺寸
其次,Al與La2O3的反應(yīng)是通過(guò)熱壓燒結(jié)過(guò)程中的固相擴(kuò)散控制的,Al2O3在點(diǎn)接觸處成核且O在Al中的擴(kuò)散速率低,使Al2O3的尺寸為納米級(jí)
最后,生成的Al2O3粗化率極低,不易長(zhǎng)大[19, 22]
進(jìn)一步的高分辨TEM觀察(圖4f)發(fā)現(xiàn),Al2O3與基體界面的結(jié)合良好
圖4復(fù)合材料的TEM照片
Fig.4TEM images of composite (a) macrostructure and Al11La3 in the matrix, (b) a selected area diffraction pattern of A-phase, (c) (d) (e) EDS mapping of the same position of (a), (f) HRTEM image of Al2O3 with its FFT in the inset, and (g) grain size
從圖4g可見(jiàn),材料的晶粒尺寸在超細(xì)晶范圍,截距法的測(cè)量統(tǒng)計(jì)結(jié)果表明,其晶粒尺寸約為350 nm
隨著材料的晶粒尺寸變小,晶粒數(shù)量和晶界增多,使室溫下位錯(cuò)的滑移變得困難,有助于使材料的強(qiáng)度提高
圖5給出了用于對(duì)比的純鋁材料的微觀組織TEM照片
通過(guò)截距法統(tǒng)計(jì)可知,材料的晶粒尺寸約為480 nm
這表明,Al11La3和Al2O3的加入進(jìn)一步促進(jìn)了基體晶粒的細(xì)化
在球磨過(guò)程中引入的部分氧,使材料中生成了少量的
氧化鋁(圖5a箭頭所示)
圖5純鋁基體的TEM照片和相同位置的能譜分析
Fig.5STEM-BF image of Al matrix (a), and EDS mapping (b, c) of the same position of (a)
2.3 室溫和350℃的高溫拉伸性能
(Al11La3+Al2O3)/Al復(fù)合材料和對(duì)比材料的室溫(Room temperature, RT)和350℃高溫拉伸曲線,如圖6所示,拉伸性能列于表1
可以看出,復(fù)合材料的室溫屈服強(qiáng)度(Yield strength, YS)為292 MPa,抗拉強(qiáng)度(Ultimate tensile strength, UTS)為328 MPa,延伸率(Elongation, EL)為10.5%;350℃屈服強(qiáng)度為113 MPa,抗拉強(qiáng)度為119 MPa,延伸率為10.2%
與用相同工藝制備的純鋁相比,復(fù)合材料的室溫和高溫抗拉強(qiáng)度分別提高了約30%和19%
同時(shí),本文制備的(Al11La3+Al2O3)/Al復(fù)合材料其性能也優(yōu)于典型的耐熱鋁合金Al-5.3Cu-0.8Mg-0.6Ag和Al-9.4Si-1.9Cu-0.5Mg,這兩種合金的350℃抗拉強(qiáng)度均低于100 MPa[6, 23, 24]
與同樣有Al2O3增強(qiáng)體的(B4C+Al2O3)/Al復(fù)合材料對(duì)比,本文制備的復(fù)合材料其高溫強(qiáng)度提升超20%[25]
圖6復(fù)合材料和鋁基體的室溫和350℃高溫抗拉曲線
Fig.6Tensile stress-strain curves of composite and Al matrix at RT (a) and 350℃ (b)
Table 1
表1
表1復(fù)合材料和鋁基體的拉伸性能
Table 1Tensile properties of composite and Al matrix
Sample
|
RT
|
350℃
|
YS/MPa
|
UTS/MPa
|
EL/%
|
YS/MPa
|
UTS/MPa
|
EL/%
|
Composite
|
292±4
|
328±3
|
10.5±0.9
|
113±5
|
119±4
|
10.2±2.2
|
Al matrix
|
208±8
|
252±3
|
18.5±1.0
|
99±6
|
100±4
|
15.2±2.0
|
(Al11La3+Al2O3)/Al復(fù)合材料室溫強(qiáng)化的主要原因:一是增強(qiáng)相Al11La3和Al2O3的載荷傳遞強(qiáng)化(?σL-T)和位錯(cuò)強(qiáng)化作用,其中位錯(cuò)強(qiáng)化主要源于Orowan強(qiáng)化(?σOro)和幾何必需位錯(cuò)強(qiáng)化(?σGND),其中Orowan強(qiáng)化效果與材料中納米顆粒的尺寸大小和體積分?jǐn)?shù)有關(guān)
隨著納米顆粒尺寸的減小和體積分?jǐn)?shù)的提高,Orowan強(qiáng)化效應(yīng)增強(qiáng);另一個(gè)是鋁基體細(xì)晶粒產(chǎn)生的晶界強(qiáng)化,可根據(jù)Hall-Petch公式計(jì)算[19, 26, 27]
根據(jù)對(duì)材料的定量分析,可求出材料各強(qiáng)化作用的貢獻(xiàn)
復(fù)合材料的屈服強(qiáng)度可表示為[25]
σyc=σym+?σAl2O3+?σAl11La3(1)
σym=σO+KHPD(2)
其中σyc為復(fù)合材料的屈服強(qiáng)度,σym為基體的屈服強(qiáng)度,?σAl2O3為Al2O3引起的強(qiáng)度增加,?σAl11La3為Al11La3引起的強(qiáng)度增加
σO為摩擦應(yīng)力(為20 MPa),KHP為Hall-Petch斜率(40 MPaμm),D為晶粒尺寸
Al2O3的強(qiáng)度提升,包含了載荷傳遞的直接強(qiáng)化(?σAl2O3L-T)、Orowan強(qiáng)化(?σAl2O3Oro)和幾何必需位錯(cuò)強(qiáng)化(?σAl2O3GND)
其中Al11La3尺寸達(dá)到微米級(jí),而材料中的Orowan強(qiáng)化主要來(lái)自于納米顆粒,因此Al11La3相的Orowan強(qiáng)化效果可忽略不計(jì)
因此,根據(jù)公式可計(jì)算出本文的復(fù)合材料與鋁基體屈服強(qiáng)度的差值為
σC-σAl=?σym+?σAl2O3+?σAl11La3(3)
?σAl2O3=?σAl2O3L-T+?σAl2O3Oro+?σAl2O3GND(4)
?σAl11La3=?σAl11La3L-T+?σAl11La3GND(5)
其中Al2O3的直接載荷傳遞的直接強(qiáng)化可表示為[28]
?σAl2O3L-T=Sσym4VAl2O3(6)
其中S為Al2O3的長(zhǎng)徑比,VAl2O3為Al2O3的體積分?jǐn)?shù)
而Al11La3的強(qiáng)化公式可簡(jiǎn)化為[29]
?σAl11La3L-T=0.5VAl11La3σym(7)
Orowan的強(qiáng)化效果可表示為[29]
?σAl2O3Oro=0.13Gbdp[12VAl2O313-1]lndp2b(8)
其中dp為增強(qiáng)顆粒尺寸,G為鋁的剪切模量(26.4 GPa),b為柏氏矢量(0.286 nm)
根據(jù)相關(guān)研究,Al2O3和Al11La3的幾何必需位錯(cuò)強(qiáng)化適用公式[25]
?σAl2O3GND=αGb8VAl2O3?ybB(9)
?σAl11La3GND=αGb8VAl11La3?ybB(10)
其中α為常數(shù)1.25,B可近似為增強(qiáng)顆粒的平均直徑,?y為屈服應(yīng)變0.2%
計(jì)算結(jié)果(列于表2)表明,原位引入的Al2O3和Al11La3對(duì)復(fù)合材料強(qiáng)度的貢獻(xiàn)值為76 MPa,與實(shí)際屈服強(qiáng)度差值84 MPa十分接近
對(duì)表2中數(shù)據(jù)的分析結(jié)果表明,Al2O3的Orowan強(qiáng)化和幾何必需位錯(cuò)強(qiáng)化作用對(duì)材料的貢獻(xiàn)較大
本文實(shí)驗(yàn)中的高球磨強(qiáng)度和高燒結(jié)溫度保障了原位反應(yīng)的充分進(jìn)行,但是燒結(jié)溫度較高使Al11La3明顯粗化,大大降低了強(qiáng)化效率
而材料的延伸率較高,表明適當(dāng)提高顆粒的含量以優(yōu)化增強(qiáng)相的數(shù)量有利于其高溫力學(xué)性能的提高
Table 2
表2
表2復(fù)合材料和鋁基體的屈服強(qiáng)度計(jì)算
Table 2Calculation of yield strength of the composite and Al matrix
/MPa?σym
|
Al2O3
|
Al11La3
|
?σL-T/MPa
|
?σOro
/MPa
|
?σGND
/MPa
|
?σL-T/MPa
|
?σOro
/MPa
|
?σGND
/MPa
|
10
|
6
|
19
|
26
|
4
|
0
|
11
|
2.4 材料斷口的形貌
材料樣品的室溫和350℃高溫拉伸斷口,如圖7所示
可以看出,復(fù)合材料的室溫拉伸斷口(圖7a)表現(xiàn)出典型的復(fù)合材料斷口形貌,在Al基體區(qū)域出現(xiàn)大量的韌窩和撕裂棱,表明基體區(qū)域的斷裂韌性很好
還發(fā)現(xiàn)許多較大的Al11La3顆粒
圖7b給出了圖7a中白色方框區(qū)域的放大圖像,可觀察到Al11La3顆粒上的裂紋
這表明,在拉伸過(guò)程中載荷傳遞使Al11La3開(kāi)裂,并可能進(jìn)一步導(dǎo)致材料斷裂
高溫拉伸斷口與室溫?cái)嗫诘牟煌卣魇牵从^察到Al11La3顆粒,表明在高溫下微米級(jí)顆粒的載荷傳遞作用減弱,難以發(fā)生界面脫粘或顆粒斷裂[30]
同時(shí), Al基體的性能在高溫下明顯惡化[31]并在拉伸過(guò)程中發(fā)生晶界滑動(dòng),因此晶界不再有強(qiáng)化作用
但是,細(xì)小的納米相可抑制晶界的滑動(dòng),從而提高材料的高溫強(qiáng)度
在沒(méi)有增強(qiáng)相的Al基體中位錯(cuò)不能形成堆積,大部分位錯(cuò)在晶界處湮滅
而復(fù)合材料中細(xì)小的納米相可與位錯(cuò)產(chǎn)生交互作用,阻礙位錯(cuò)運(yùn)動(dòng)
因此,需要更多的能量才能使材料進(jìn)一步的變形,從而提高了材料的強(qiáng)度
但是,納米相的釘扎作用使位錯(cuò)堆積和應(yīng)力集中,從而產(chǎn)生材料的沿晶斷裂
高溫?cái)嗫诔尸F(xiàn)出明顯的沿晶斷裂特征,且表面存在大量的納米顆粒(圖7c,d),與上述文獻(xiàn)報(bào)道相同
圖7復(fù)合材料的室溫和350℃拉伸斷口的SEM照片
Fig.7SEM fractographs at RT (a, b) and 350℃ (c, d) for composites
3 結(jié)論
(1) 在鋁粉中添加質(zhì)量分?jǐn)?shù)為8%的La2O3顆粒并用原位反應(yīng)可制備(Al11La3+Al2O3)/Al復(fù)合材料
較高的球磨強(qiáng)度是激活原位反應(yīng)的重要因素,在630℃燒結(jié)過(guò)程中原位反應(yīng)基本完全,生成了微米級(jí)Al11La3和納米級(jí)Al2O3
(2) (Al11La3+Al2O3)/Al復(fù)合材料的室溫強(qiáng)化機(jī)制主要為Al11La3和Al2O3的位錯(cuò)強(qiáng)化和載荷傳遞強(qiáng)化,而在高溫下Al11La3的載荷傳遞作用減弱,強(qiáng)化機(jī)制是納米Al2O3對(duì)晶界的釘扎
(3) (Al11La3+Al2O3)/Al復(fù)合材料的350℃抗拉強(qiáng)度達(dá)到119 MPa并具有良好的延伸率,其性能優(yōu)于目前應(yīng)用在高溫下的Al-Cu-Mg-Ag和Al-Si-Cu-Mg鋁合金
參考文獻(xiàn)
View Option 原文順序文獻(xiàn)年度倒序文中引用次數(shù)倒序被引期刊影響因子
[1]
Chak V, Chattopadhyay H, Dora T L.
A review on fabrication methods, reinforcements and mechanical properties of aluminum matrix composites
[J]. J. Manuf. Process., 2020, 56: 1059
DOIURL [本文引用: 1]
[2]
Mavhungu S T, Akinlabi E T, Onitiri M A, et al.
Aluminum matrix composites for industrial use: advances and trends
[J]. Procedia Manufacturing, 2017, 7: 178
DOIURL [本文引用: 1]
[3]
Hu H E, Zhen L, Yang L, et al.
Deformation behavior and microstructure evolution of 7050 aluminum alloy during high temperature deformation
[J]. Mater. Sci. Eng. A, 2008, 488(1-2): 64
DOIURL [本文引用: 1]
[4]
Guo X, Tao L, Zhu S, et al.
Experimental Investigation of Mechanical Properties of Aluminum Alloy at High and Low Temperatures
[J]. J. Mater. Civ. Eng., 2020, 32(2): 06019016
[本文引用: 1]
[5]
Jeong C Y.
High temperature mechanical properties of Al-Si-Mg-(Cu) alloys for automotive cylinder heads
[J]. Mater. Trans., 2013, 54(4): 588
DOIURL [本文引用: 1]
[6]
Mohamed A M A, Samuel F H, Kahtani S A.
Microstructure, tensile properties and fracture behavior of high temperature Al-Si-Mg-Cu cast alloys
[J]. Mater. Sci. Eng. A, 2013, 577: 64
DOIURL [本文引用: 2]
[7]
Skinner D J, Bye R L, Raybould D, et al.
Dispersion strengthened Al-Fe-V-Si alloys
[J]. Scripta Metallurgica, 1986, 20(6): 867
DOIURL [本文引用: 1]
[8]
Barmouz M, Besharati Givi M K, Seyfi J.
On the role of processing parameters in producing Cu/SiC metal matrix composites via friction stir processing: Investigating microstructure, microhardness, wear and tensile behavior
[J]. Mater. Charact., 2011, 62(1): 108
DOIURL [本文引用: 1]
[9]
Zan Y N, Zhang Q, Zhou Y T, et al.
Enhancing high-temperature strength of B4C-6061Al neutron absorber material by in-situ Mg(Al)B2
[J]. J. Nucl. Mater., 2019, 526: 151788
DOIURL
[10]
Jiang L, Li Z, Fan G, et al.
Strong and ductile carbon nanotube/aluminum bulk nanolaminated composites with two-dimensional alignment of carbon nanotubes
[J]. Scr. Mater., 2012, 66(6): 331
DOIURL
[11]
Li M, Gao H, LianG J, et al.
Microstructure evolution and properties of graphene nanoplatelets reinforced aluminum matrix composites
[J]. Mater. Charact., 2018, 140: 172
DOIURL [本文引用: 1]
[12]
Wang H, Li G, Zhao Y, et al.
In situ fabrication and microstructure of Al2O3 particles reinforced aluminum matrix composites
[J]. Mater. Sci. Eng. A, 2010, 527(12): 2881
DOIURL [本文引用: 1]
[13]
Zhu H, Min J, Li J, et al.
In situ fabrication of (α-Al2O3+Al3Zr)/Al composites in an Al-ZrO2 system
[J]. Compos. Sci. Technol., 2010, 70(15): 2183
DOIURL [本文引用: 1]
[14]
Feng C F, Froyen L.
Formation of Al3Ti and Al2O3 from an Al-TiO2 system for preparing in-situ aluminium matrix composites
[J]. Compos. Pt. A-Appl. Sci. Manuf., 2000, 31(4): 385
DOIURL
[15]
Rong X, Zhao D, He C, et al.
Revealing the strengthening and toughening mechanisms of Al-CuO composite fabricated via in-situ solid-state reaction
[J]. Acta Mater., 2021, 204: 116524
DOIURL [本文引用: 1]
[16]
Anthony A I, Suzuki A, Kamado S, et al.
Optimization of Mg-Zn-Al-Ca-La Alloys for the Improvement of Casting Properties and Creep Resistance
[J]. Materials Science Forum, 2005, 488-489: 805
DOIURL [本文引用: 1]
[17]
Colombo M, Gariboldi E, Morri A.
Influences of different Zr additions on the microstructure, room and high temperature mechanical properties of an Al-7Si-0.4Mg alloy modified with 0.25%Er
[J]. Mater. Sci. Eng. A, 2018, 713: 151
DOIURL
[18]
Khomamizadeh F, Nami B, Khoshkhooei S.
Effect of rare-earth element additions on high-temperature mechanical properties of AZ91 magnesium alloy
[J]. Metall. Mater. Trans. A, 2005, 36(12): 3489
DOIURL
[19]
Chen C F, Kao P W, Chang L, et al.
Mechanical properties of nanometric Al2O3 particulate-reinforced Al-Al11Ce3 composites produced by friction stir processing
[J]. Mater. Trans., 2010, 51(5): 933
DOIURL [本文引用: 3]
[20]
Sakamoto T, Kukeya S, Ohfuji H.
Microstructure and room and high temperature mechanical properties of ultrafine structured Al-5%Y2O3 and Al-5%La2O3 nanocomposites fabricated by mechanical alloying and hot pressing
[J]. Metall. Mater. Trans. A, 2019, 748: 428
[本文引用: 4]
[21]
Choi H J, Shin J H, Bae D H.
The effect of milling conditions on microstructures and mechanical properties of Al/MWCNT composites
[J]. Compos. Pt. A-Appl. Sci. Manuf., 2012, 43(7): 1061
DOIURL [本文引用: 1]
[22]
Chao Z L, Zhang L C, Jiang L T, et al.
Design, microstructure and high temperature properties of in-situ Al3Ti and nano-Al2O3 reinforced 2024Al matrix composites from Al-TiO2 system
[J]. J. Alloy. Compd., 2019, 775: 290
DOI [本文引用: 1]
This study was conducted to obtain a type of aluminum matrix composites exhibiting a good strength and certain ductility at high temperature. The 25 vol% TiO2-75 vol%2024 Al systems were selected to fabricate the (Al3Ti+Al2O3)/2024 Al composites with residual similar to 32 vol% Al matrix through powder metallurgy. The (Al3Ti+Al2O3)/2024 Al exhibits a good strength and certain ductility at high temperature as in the design. The microstructure of (Al3Ti+Al2O3)/2024 Al composites was investigated. It was discovered that the in-situ Al3Ti reinforcement was in coarse block-shaped particles of approximately 6.9 mu m in size and the Al-Al3Ti interface was clean. The Al2O3 particles were in the nano-scale and distributed in the Al matrix in a cluster form. The high temperature compression testing of the composites was conducted at the temperatures of 573 K, 623 K, 673 K, 723 K and 773 K with the strain rate of 10(-3) similar to 0.42 s(-1). The results demonstrated that the composites exhibited higher strength at the same high temperature than the other Al matrix composites with a similar volume fraction. The massive Al3Ti and Al2O3 phases played a load bearing role at high temperatures. The residual similar to 32 vol% Al matrix led the composites to acquire certain ductility. (C) 2018 Elsevier B.V.
[23]
Zuo L, Ye B, Feng J, et al.
Effect of Q-Al5Cu2Mg8Si6 phase on mechanical properties of Al-Si-Cu-Mg alloy at elevated temperature
[J]. Mater. Sci. Eng. A, 2017, 693: 26
DOIURL [本文引用: 1]
[24]
Xiao D H, Wang J N, Ding D Y, et al.
Effect of rare earth Ce addition on the microstructure and mechanical properties of an Al-Cu-Mg-Ag alloy
[J]. J. Alloy. Compd., 2003, 352(1-2): 84
DOIURL [本文引用: 1]
[25]
Zan Y N, Zhou Y T, Zhao H, et al.
Enhancing high-temperature strength of (B4C+Al2O3)/Al designed for neutron absorbing materials by constructing lamellar structure
[J]. Compos. Pt. B-Eng., 2020, 183: 107674
DOIURL [本文引用: 3]
[26]
Hansen N.
Hall-Petch relation and boundary strengthening
[J]. Scr. Mater., 2004, 51(8): 801
DOIURL [本文引用: 1]
[27]
Ma K, Wen H, Hu T, et al.
Mechanical behavior and strengthening mechanisms in ultrafine grain precipitation-strengthened aluminum alloy
[J]. Acta Mater., 2014, 62: 141
DOIURL [本文引用: 1]
[28]
Nardone V C, Prewo K M.
On the strength of discontinuous silicon carbide reinforced aluminum composites
[J]. Scripta Metallurgica, 1986, 20(1): 43
DOIURL [本文引用: 1]
[29]
Zhang Z, Chen D.
Consideration of Orowan strengthening effect in particulate-reinforced metal matrix nanocomposites: A model for predicting their yield strength
[J]. Scr. Mater., 2006, 54(7): 1321
DOIURL [本文引用: 2]
[30]
Zan Y N, Zhou Y T, Liu Z Y, et al.
Microstructure and mechanical properties of (B4C+Al2O3)/Al composites designed for neutron absorbing materials with both structural and functional usages
[J]. Mater. Sci. Eng. A, 2020, 773: 138840
DOIURL [本文引用: 1]
[31]
Poletti C, Balog M, Simancik F, et al.
High-temperature strength of compacted sub-micrometer aluminium powder
[J]. Acta Mater., 2010, 58(10): 3781
DOIURL [本文引用: 1]
A review on fabrication methods, reinforcements and mechanical properties of aluminum matrix composites
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