- Volume 35,Issue 6,2006 Table of Contents
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Fan Jinglian , Liu Tao , Cheng Huichao , Huang Baiyun
2006, 35(6):841-844.
Abstract:鎢合金與貧鈾彈相比,在穿甲過程中由于形成“蘑菇頭”而不能形成很好的絕熱剪切帶而使其穿甲性能不及貧鈾彈.鎢合金在高速沖擊加載下的動態(tài)力學性能和失效決定著鎢合金穿甲性能,為此,本文綜述了十多年來國內外對鎢合金在高速沖擊加載下的動態(tài)力學性能和失效機理的研究現狀.
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Hu Rui , Zhang Huangli , Geng Xinguo , Li Jinshan , Fu Hengzhi , Feng Yong , Zhang Pingxiang , Zhou Lian
2006, 35(6):845-849.
Abstract:Large bulk HTS single crystal can be used to measure accurately the structure and understand the relation between crystal structure and properties, as well as to obtain more information on its nature for high Tc superconductor. It is important to understand and explain the mechanism of high Tc superconductivity and their applications. It is quite difficult to obtain a large bulk HTS single crystal due to peritectic reaction, peritectic transformation and incoordinate composition transformation in the crystal growth process of HTS oxides, especially, a liquid-solid line of steep slope in YBCO phase diagram. Crystal growth theory related to HTS single crystal grown and techniques, some effects and improvements for crystal growth were discussed in this paper. In addition, some techniques for preparing HTS single crystal were summarized.
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2006, 35(6):850-854.
Abstract:Recent developments on laser cladding of titanium and its alloys are reviewed. The research progresses on the clad layer with enhanced wear resistance, the improved biocompatibility, the composite clad layer, the functionally gradient clad layers and the laser rapid forming process of titanium alloys are summarized. Some problems to be solved are suggested for the study of laser cladding on titanium alloys.
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Liu Weidong , Qu Hua , Zhou Yu , Liu Zhiling
2006, 35(6):855-859.
Abstract:在TiAl基合金相空間與相界面價電子結構計算的基礎上,利用表征相結構單元成鍵能力的相結構因子F與表征界面結合強度的界面結合因子△ρ給出了一種計算TiAl基合金屈服強度的方法.該方法以實驗數據為基礎,進行回歸分析求α2相體積分數,以理論屈服強度與實際屈服強度之差是否滿足一級近似作為合金基體γ相強度σs^γ-TiAl取值的判據,用相結構單元最強鍵上的共用電子對數nA計算Nb在γ相與α2相中的含量Wγ^Nb和Wα2^Nb.計算了全片層TiAl,TiAl-8Nb,TiAl-10Nb合金的屈服強度,與實測值比較,理論計算結果令人滿意.
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Peng Dequan , Bai Xinde , Chen Baoshan
2006, 35(6):860-865.
Abstract:為了研究碳離子注入對純鋯耐蝕性的影響,用MEVVA源對純鋯樣品進行了1×1016ions/cm2至1×1017ions/cm2的碳離子注入,注入加速電壓為40 kV.用X射線光電子能譜(XPS)和俄歇電子譜(AES)分析了注入樣品表層元素的價態(tài)和深度分布.透射電鏡(TEM)用來觀察碳離子注入樣品的微觀結構;碳離子注入樣品后相結構的變化用掠角X射線衍射(GAXRD)來檢測.純鋯注入樣品隨后浸入1 mol/L的硫酸溶液中,測其極化曲線以評價其耐蝕性.發(fā)現碳離子注入極大地提高了純鋯基體的耐蝕行為,劑量越高,耐蝕性越好.最后,對碳離子注入導致純鋯基體腐蝕行為發(fā)生改變的機理進行了討論.
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Ouyang Hongwu , Chen Xin , Yu Wentao , Huang Baiyun
2006, 35(6):866-870.
Abstract:研究了緊耦合氣霧化制粉過程中AlNiY合金熔滴的冷卻行為以及非晶顆粒的形成機制.結果表明：（1）AlNiY合金非晶化的臨界冷卻速率大致為10^3K/s;（2）熔滴的冷卻速率與直徑成反比,當直徑小于25 μm時,熔滴達到臨界冷卻速率實現非晶化.當直徑大于25μm時,熔滴無法獲得非晶化臨界冷卻速率,只能發(fā)生形核結晶;（3）熔滴的非晶化還與霧化過程相關,由于熔滴破碎時的位置和溫度不同,獲得的冷卻速率將不同,出現了相同直徑（小于25 μm）的顆粒存在非晶和結晶兩種狀態(tài).
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Zhou Dianwu , Peng Ping , Hu Yanjun , Liu Jinshui
2006, 35(6):871-875.
Abstract:The energy and electronic structure of several Mg-Ce intermetallic compounds with different structure types were investigated using the first-principle pseudopotential plane-wave method. Based on the calculations of formation heat of and cohesive energies, their structural stability was analyzed. The results show that the structure types with the strongest alloying ability and the highest structural stability are DO3, C15, Ba, C15 and DO3, respectively, for the Mg3Ce, Mg2Ce, MgCe, MgCe2, MgCe3 intermetallic compounds. After compared the DOS (density of state) of these phases with different structure types, the results show that the discrepancy in structural stability of Mg-Ce intermetallic compounds can be attributed to the difference in the bonding electron numbers at Feimi level, which mainly originates from the contribution of valence electrons of Mg(3s), Mg(2p), Ce(5d) and Ce(4f) orbits. The less the valence electrons at Feimi level, the better the structural stability of Mg-Ce intermetallic compounds.
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Wang Ping , Kang Hao , Shi Lifeng , Lu Guimin , Cui Jianzhong
2006, 35(6):880-884.
Abstract:采用AnyCasting軟件模擬研究了模具內澆口尺寸、壓射速度等因素對半固態(tài)ZL201合金觸變壓鑄充型過程的影響.結果表明：壓鑄溫度640℃,模具溫度200℃～240℃,內澆口厚度11mm,低速階段的壓射速度0.1 m/s,高速階段的壓射速度1 m/s,在充型60%時進行速度切換,半固態(tài)漿料將以層流方式充填型腔,模擬結果與實際符合很好.半固態(tài)壓鑄件經T5處理后,硬度（HV）可達到1166 MPa,高于常規(guī)壓鑄件45.7%.
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Dong Ping , Li Ruiwen , Jiang Fan , Chen Piheng
2006, 35(6):885-889.
Abstract:The thermal stress for Al/Ti coatings on uranium substrate was analyzed by using a thermal elastic plastic finite element method (FEM). The results indicate that the thermal stress is compressive inside the Ti coating and tensile inside the Al coating, which reaches the yield strength of Al. There is an uneven thermal stress distribution at the free side of specimen due to the end effect, which is vanished gradually at about 2h (where h is the coating thickness) from the free side of specimen. The shear stress of U-Al at the free side is larger than that in the middle of specimen. The effect of deposition temperature, coating thickness and mechanical properties on the thermal stress and plastic strain in coatings were also investigated. The results show that the thermal stress and plastic strain increase remarkably with the deposition temperature increasing. It is helpful to decrease the thermal stress and plastic strain by decreasing the thickness of Al coating and increasing the thickness of Ti coating. The yield strength of Al coating and the elastic modulus of Ti coating have large effects on the thermal stress and plastic strain of the coatings.
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Wu Yanqing , Niu Lisha , Shi Huiji , Wang Zhanhong
2006, 35(6):890-894.
Abstract:用原位SEM觀測研究了粉末冶金B(yǎng)eAl材料應力控制的疲勞機制.斷裂時,低應力疲勞比高應力的平均累積塑性應變小得多.前者的累積塑性應變變化速率隨著循環(huán)次數增大明顯減小,后者則接近線性變化規(guī)律,表明高應力水平下的疲勞損傷累積更接近線性假設.低應力疲勞可從表面觀測到一條疲勞主裂紋,由微觀尺度下的累積塑性應變控制;高應力水平疲勞加載初期很快有宏觀尺度的累積塑性應變,使Be與Al結合相界面同時產生較多裂紋.裂紋主要沿Al和Be結合強度較弱的表面路徑擴展,隨后沿縱深方向擴展,在材料內部裂紋擴展方向會變?yōu)榕c加載方向平行的Be基滑移面方向.當裂紋達到臨界尺寸,局部塑性應變控制變?yōu)橹鲬Ψ较蚩刂?促使裂紋向前方擴展,宏觀斷口呈現出有層次的撕裂型.
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Hu Shaoqiu , Zeng Sumin ,
2006, 35(6):895-899.
Abstract:建立了幾何拓撲模型和熱應力拓撲模型,從這2種拓撲模型的結構、形狀和對稱性、特別是多次對稱軸之間的關系,深入分析了角端、邊緣、表層、內部4種淬火模型以及淬火角端效應和動態(tài)薄膜效應之間的內在聯系,并指出了各種具體的工業(yè)實際應用.淬火過程中,熱力學拓撲模型的對稱軸(特別是n次對稱軸)將以變化的θ角圍繞幾何拓撲模型的對稱軸(特別是n次對稱軸)不停轉動,θ的大小由幾何拓撲模型和動態(tài)薄膜共同決定,θ=0°或θ很小時,是理想狀態(tài)層狀分布熱應力,θ較大甚至接近90°時,發(fā)生淬火角端效應和淬火動態(tài)薄膜效應.并且熱力學拓撲模型的對稱軸(特別是n次對稱軸)指向的表面出現拉應力,和該軸成垂直方向的表面出現壓應力.
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Zhang Hongjie , Zhao Yutao , Dai Qixun , Li Guirong , Wang Xiaoyan , Zhang Zhao
2006, 35(6):905-909.
Abstract:以氧氯化鋯(ZrOCl2·8H2O)為反應物,采用熔體反應法,并在反應過程中施加脈沖渦流磁場,磁化學合成了(Al2O3+Al3Zr)p/Al復合材料.掃描電鏡(SEM)與X射線衍射(XRD)分析表明生成的顆粒為α-Al2O3和Al3Zr,顆粒細小,形狀一致,且彌散分布于鋁基體中;在相同反應條件下,與常規(guī)原位反應相比,磁場下反應更快、更完全,縮短了反應時間,并從反應動力學角度進行了分析.復合材料的力學性能研究表明,其屈服強度σs和抗拉強度σb均隨顆粒體積分數的增加而升高,延伸率δ先升后降.(Al2O3+Al3Zr)p/Al復合材料的拉伸斷口形貌表明,其斷裂屬塑性斷裂.
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Dai Xiaoyuan , Xia Changqing , Liu Changbin
2006, 35(6):913-916.
Abstract:研究了微量鈧對Al-Zn-Mg-Cu-Zr合金組織性能的影響,鈧在鋁合金中主要以2種形式的化合物存在,一種是合金凝固時從熔體中析出的一次Al3（Sc,Zr）相,另一種是合金鑄錠均勻化時析出的二次Al3（Sc,Zr）相,前者是α（Al）晶粒細化劑,有效細化鑄態(tài)晶粒,而二次Al3（Sc,Zr）粒子強烈釘扎晶粒內位錯及亞晶界,有效阻止熱軋、退火或固溶處理過程中合金再結晶.鈧是產生強烈析出強化效應的合金元素,含0.30%Sc的Al-Zn-Mg-Cu-Zr合金的抗拉強度和延性顯著高于不加鈧的鋁合金.
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Luo Fenghua , Chen Jiaya , Tao Yuqiang , Katsunari Oikawa , Kiyohito Ishida
2006, 35(6):917-920.
Abstract:用金相顯微分析、DSC和VSM方法研究了Co40.5Ni34Al25.5合金馬氏體相變和Curie點隨淬火溫度的變化,通過三點彎曲試驗研究其形狀記憶效果.結果發(fā)現該合金馬氏體相變溫度和Curie點與淬火溫度成正比關系.馬氏體相變的4種溫度,即Ms,Mf,As和Af基本平行變化,淬火溫度每升高10℃,馬氏體相變溫度和Curie點升高8℃～9℃.β相中Al的含量隨淬火溫度升高而降低,因而使馬氏體相變溫度和Curie點升高.1320℃淬火的Co40.5Ni34Al25.5合金的彎曲強度約為450 MPa,彎曲試驗表明Co40.5Ni34Al25.5合金有雙向形狀記憶特性.
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Geng Xingguo , Li Jinshan , Fu Hengzhi , Liu Qian , Su Kehe , Zhang Cuiping , Zhou Lian
2006, 35(6):921-924.
Abstract:The LUMO-HOMO energy gaps in YBa2Cu3O7 have been calculated with density functional method (DFT) on a cluster model of unit cell in a wide range of temperatures (5 K~300 K). The results show that the superconducting energy gap (2?(T)) is about 80 meV at Tc (93 K), and decreases smoothly as the temperature increasing. It reaches the minimum at Tc and exhibits pseudogap above Tc. The pseudogap value reaches the maximum at T*(120 K) when the temperature increasing. The calculations by the cluster model of YBa2Cu3O6 unit cell show that the energy gap is about 102meV with characteristic gap of semiconductor.
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Liu Ying , Chen Weiping , Zhang Weiwen , Zhang Wen , Li Yuanyuan
2006, 35(6):925-928.
Abstract:研究了稀土、鈣元素低合金化對AZ31鎂合金板材力學性能、彎曲及拉脹復合成形性能的影響.結果表明：加入0.3%RE,0.3Ca%（質量分數,下同）后,AZ31鎂合金板材的晶粒較細、力學性能明顯提高,300℃,4 h退火后室溫抗拉強度為284 MPa、延伸率為23.2%：同時,該合金板材具有最好的彎曲及拉脹復合成形性能,隨著溫度的提高其成形性能進一步提高.
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Yang Shulin , Sun Wenru , Wang Zhaokun , Zhang Yindong , Wei Zhigang , Hu Zhuangqi
2006, 35(6):929-932.
Abstract:當GH761合金中的硼含量控制在正常值時,將磷含量從0.007%提高到0.023%,合金的650℃/637 MPa持久壽命從245 h提高到975 h,增幅達3倍.保持磷含量為0.023%,將硼含量提高到0.011%或以上時,合金的持久壽命顯著降低.在實驗含量范圍內,磷、硼對合金的室溫拉伸和650℃拉伸均無明顯影響.磷、硼的最佳控制含量位于0.023%和0.005%附近.分析表明,當硼含量為正常值時,適量提高磷含量有助于改善合金的晶界析出,提高合金的持久性能.當加入適量磷時,進一步提高硼含量,將導致晶界析出過量,降低持久性能.
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Zhang Jiuxing , Zhang Guozhen , Zhang Liping , Wang Che , Song Xiaoyan , Zhou Moiling , Zhong Taoxing
2006, 35(6):937-940.
Abstract:The WC bulk was in-situ synthesized with mixed WO3 +14.5%C powders by spark plasma sintering at different temperatures. The chemical valence state of W, C, O in the samples were investigated by XPS. The results indicates that the element W changes from W+6, W+5, W+4 in oxidative state to metallic W0 and W+2 in carbide state with the rising of synthesizing temperature. It reveals that WO3 is firstly reduced by carbon to form intermediate tungsten oxides such as WO2.72, WO2, and metallic W in the reduction process, then the carbonization reaction occurs, and the WC is formed finally.
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Wei Qilong , Wang Yongxin , Chen Zheng
2006, 35(6):941-944.
Abstract:以Al-Li合金為對象,通過DSC技術研究了合金的相變.確定了相變溫度范圍、類型及其微觀機理,確立了相變動力學計算方法,并以此計算了δ＇相的析出和溶解的激活能.研究表明：δ＇相析出為一級反應機制、δ＇相溶解則為三維擴散機制;在本實驗條件下,δ＇相的析出激活能為188 kJ/mol～214 kJ/mol,δ＇相的溶解激活能為158 kJ/mol～228kJ/mol.根據實驗和分析,可以認為采用熱分析動力學方法能定量地表征Al-Li合金的相變.
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Shen Xiangqian , Jing Maoxiang , Wang Taoping , Cao Kai
2006, 35(6):945-949.
Abstract:分別以檸檬酸和堿式碳酸鎳、乳酸和硝酸鐵為原料,采用有機凝膠-熱還原法分別成功制備了超細（直徑＜1 μm）金屬鎳纖維和鐵纖維,鎳纖維長2 m,鐵纖維長0.5 m,組成2種纖維的晶粒約100 nm.通過FTIR,XRD,TG/DSC和SEM對纖維前驅體凝膠的結構、熱分解過程及熱還原產物的形貌進行了表征.凝膠的可紡性與組成凝膠的羧酸鹽分子結構有關.檸檬酸和乳酸中的羥基分別單齒配位于Ni^2＋和Fe^3＋離子,可能形成線型分子[（C6H6O7）Ni]n和[C3H4O3]3Fe,由這些線型分子組成的凝膠顯示出了良好的可紡性.同時,可能由于在檸檬酸與Ni2＋離子的反應中存在Ni2＋離子的架橋作用,因而檸檬酸鎳凝膠顯示出了比乳酸鐵凝膠更好的可紡性.
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Xu Jinzhang , Zhang Zhihua , Wang Yuhua
2006, 35(6):950-953.
Abstract:以H3BO3作助熔劑,用高溫固相法在1400℃、保溫4 h的條件下成功制備了LaMgAl11O19：Tb單相粉末樣品并研究了其紫外光、真空紫外光激發(fā)下的一系列發(fā)光特性.在紫外光（254 nm）、真空紫外光（147 nm）激發(fā)下,觀察到Tb^3＋很強的^5D4→^7FJ（=6,5,4,3）的躍遷發(fā)光.分析了LaMgAl11O19：Tb^3＋的發(fā)光強度與Tb^3＋摻雜濃度的關系.
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Peng Jucun , Lu Qianghua , Wu Boying
2006, 35(6):954-958.
Abstract:對金溶膠的水相合成工藝中的攪拌時間以及試劑的加入量進行了實驗研究,探討了攪拌時間對金溶膠特征參數和穩(wěn)定性的影響.研究中發(fā)現金溶膠制備完畢后,繼續(xù)攪拌會破壞金溶膠的穩(wěn)定.在所配的試劑濃度的條件下,檸檬酸鈉溶液的用量在不大于2 ml時都可以制備穩(wěn)定的金溶膠,并且金溶膠的吸光度隨氯金酸用量的增加而線性增加.
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Yang Xiaohong , Wu Qingsheng , Ding Yaping , Zhang Guoxin
2006, 35(6):959-962.
Abstract:在以Triton X-100為表面活性劑形成的反相膠束體系中,成功地制備了半導體硫化銀納米管,管徑88 nm～120nm、長度大于2.6 μm.X射線衍射測定表明,產物為純單斜結構.紫外-可見光譜在275 nm處發(fā)現新的吸收峰,最大發(fā)射波長與體相材料相比,藍移了38 nm.
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Feng Wangjun , Xia Tiandong , Liu Tianzuo , Zhao Wenjun , Wei Zhiqiang
2006, 35(6):963-965.
Abstract:用自蔓延(SHS)法成功制備了MgB2超導塊材.B,Mg合成MgB2是放熱反應,預熱溫度和真空度是影響MgB2性能的主要因素,當預熱溫度太低時不能用電弧引導反應,理論計算和實驗結果表明預熱溫度應該大于484 K,但預熱溫度太高會使部分MgB2分解為MgB4和MgB7,當預熱溫度為520K,真空度為2.4×10-3Pa時,試樣的臨界溫度Tc=38.45K,溫度轉變寬度小于0.4 K,臨界電流密度Jc=1.60×106A/cm2(10 K,0.5 T),1.65×106A/cm2(20 K,0 T).試樣的致密度較低時,結構為層狀,層與層之間有空洞,每層由顆粒狀晶粒組成,顆粒尺寸為2 μm～5 μm.SHS法制備MgB2超導塊材工藝簡單、反應時間短(3 s～5 s).
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Yang Li , Zhou Yi , Zhang Guoyan , Liao Huailin , Huang Ru , Zhang Xing , Wang Yangyuan
2006, 35(6):966-969.
Abstract:A backside growth technique of thick porous silicon layers for the on-chip RF integrated inductor is presented. ASITIC calculation confirms that the thick porous silicon substrate (through the wafer) is a better choice to achieve high quality factor RF integrated inductors. Fabrication and characterization of the through wafer PS layer with the backside growth technique were carried out, which proved the feasibility of post-processing procedure in CMOS technology. ESEM was used to observe the morphologies of the fabricated samples. The relationships of PS growth rate as a function of current density was concluded.
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2006, 35(6):970-973.
Abstract:借助金相顯微鏡研究了Sr對AZ91鎂合金鑄態(tài)顯微組織的影響.結果表明,少量的Sr（0.2%～0.5%,質量分數,下同）對合金的鑄態(tài)組織具有明顯細化作用,并增加合金的密度.進一步增加Sr含量,合金組織有粗化傾向,而且形成桿狀Al4Sr新相.利用差熱分析和電子探針研究了合金鑄態(tài)組織的細化機制.
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Zhao Lidong , He Dingyong , K. Bobzin , E. Lugscheider
2006, 35(6):974-977.
Abstract:采用高速火焰（HVOF）熱噴涂工藝制備了金屬間化合物NiAl-Ta-Cr涂層.研究了噴涂距離、氧氣流量以及燃氣流量等工藝參數對涂層組織結構和性能的影響.用光學顯微鏡觀察涂層的組織結構并測定涂層的孔隙率,用LECOTC316氣體抽提儀檢測涂層的氧含量.結果表明,氧氣流量、噴涂距離等工藝參數對涂層性能的影響比較明顯.隨著噴涂距離的增加,涂層的氧含量降低;O/H比率越大,涂層的氧含量越高,而孔隙率降低,沉積率越高.涂層經1100℃,4 h真空熱處理后,變得更加均勻和致密,孔隙率降低,但涂層的硬度有所降低.涂層經1100℃,100 h高溫氧化處理后,在涂層表面生成了連續(xù)的氧化鋁氧化層,硬度比真空退火后略有下降.
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Wang Jianfeng , Song Zhongxiao , Xu Kewei , Fan Duowang
2006, 35(6):978-981.
Abstract:The Nb-Si-N films were deposited by reactive magnetron sputtering with different N2 partial pressures. The result showed that the composition, microstructure and properties of the Nb-Si-N films depend strongly on the N2 partial pressure. As the N2 partial pressure increasing, the Nb/Si ratio and the surface roughness decease, but the bulk resistance and microhardness of the Nb-Si-N films increase. The microstructure of Nb-Si-N films is a nano-composite structure consisting of nano-sized NbN crystallites and amorphous Si3N4-like compound of Si-N. With the increase of N2 partial pressure, the amorphous tendency of Nb-Si-N films increases and the grain size decreases.
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Xiao Qunfang , Ning Xiaoshan , Zhou Heping , Yang Lei
2006, 35(6):982-985.
Abstract:The effects of stir velocity, slurry viscosity and density on the porosity were studied and the porosity was characterized by using the Reynolds number according to the bubble forming theory in this paper. It is found that the porosity is the same if the Reynolds number is the same regardless different stir velocity, slurry viscosity or slurry density. The quantitative functional relationships between the porosity and Reynolds number was deduced.
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Deng Lianwen , He Huahui , Feng Zekun , Jiang Jianjun , Zhang Xiucheng , Xiong Weihao
2006, 35(6):986-989.
Abstract:研究在微波段具有高磁導率和大磁損耗的CoFeZrRE薄膜,采用射頻磁控濺射工藝制備該類薄膜,探討了工藝參數和薄膜厚度對CoFeZrRE薄膜結構和電磁性能的影響.重點研究了摻雜稀土元素的含量和種類對薄膜磁各向異性、飽和磁化強度等基本磁參量以及微波磁導率和磁損耗的影響.結果表明,重稀土元素（如Dy,Tb）提高微波磁損耗的效果更顯著;CoFeZrRE類薄膜具有較高的微波磁導率和磁損耗（2 GHz處,μ＇和μ＂均高于200）,有望在微波吸收和抗電磁干擾領域獲得廣泛應用.
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Yin Na , Wang Chengjian , Liu Xueyan , Hou Zhi
2006, 35(6):990-993.
Abstract:The La2NiO4 metalloid conductive ceramics produced by conventional ceramic preparation technique were added into fine silver powders to form Ag/La2NiO4 composite contact materials. It is found by XRD that the phase structure of La2NiO4 ceramics did not change after arc erosion and exhibited a high chemical stability. The test results of model life and mechanical and physical properties show that the mass transfer and erosion is less and the performance of surface anti-erosion is more favorable for the contacts, resulting in the small resistivity and good mechanical properties. The Ag/La2NiO4 contacts exhibit an excellent performance compared with the Ag/CdO and Ag/SnO2 contact materials and very possible for the new type of contact materials as environmentally acceptable alternative to Ag/CdO.
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Zhou Jun , Chu Chenglin , Zhong Zhiyuan
2006, 35(6):994-997.
Abstract:The surface structure was characterized by XRD, SEM, XPS and FTIR for the NiTi shape memory alloy (SMA) with a nearly-equiatomic ratio after composite bioactive treatment in H2O2 and subsequent NaOH solutions. The biomimetic deposition process of apatite coatings on the pretreated NiTi SMA was studied in the simulated body fluid (SBF). The experimental results indicate that a wormlike bioactive layer with many Ti-OH groups and a trait of Ni2O3 is formed on the NiTi substrate after the composite bioactive treatment, which was mainly composed of the poorly-crystallized Na2TiO3 and TiO2 and relatively poor in Ni. The bioactive layer can induce the apatite nucleation and growth in SBF and obtain an ideal apatite coating on NiTi substrate in a short term.
>材料工藝
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Zhang Jing , He Lin , Sun Jun
2006, 35(6):998-1001.
Abstract:采用電弧爐坩堝澆鑄法制備Zr50Cu40Al10三元鋯基塊體非晶,研究了電磁攪拌合金熔體的作用.結果表明,雖然在該方法中合金熔體是僅在重力作用下自由充填鑄模型腔,但與常用的真空吸鑄銅模鑄造法相比,鑄模對合金熔體的激冷能力并沒有明顯的降低.電磁攪拌可減小合金熔體與坩堝底部由于歐姆接觸所造成的“晶核污染”,因而使鋯基塊體非晶態(tài)合金具有更寬的過冷液相區(qū)溫度范圍△Tx和更高的熱穩(wěn)定性.
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Li Juan , Bai Xinde , Zhang Dailan
2006, 35(6):1002-1005.
Abstract:利用電化學極化曲線測量、氧化增重測量、往復式摩擦磨損實驗,對分別通過陽極氧化和高壓釜氧化生成的2種不同Zr-4合金表面氧化膜的耐腐蝕、耐高溫氧化和抗摩擦性能進行測試和對比評價.實驗表明,2種氧化膜都有效地改善了Zr-4合金的性能（耐腐蝕,耐高溫氧化等）,它們對Zr-4合金的改善程度相近.XRD,XPS,RBS,SEM等方法分析表明,陽極氧化膜厚度約1μm,分為疏松水合層和ZrO2致密層2部分,ZrO2由四方相和單斜相組成;高壓釜預生膜厚度約0.9μm,分為最外H2O層、疏松水合層和ZrO2致密層3部分,ZrO2只以單斜相存在.研究結果為現行核工業(yè)中對Zr-4合金的預處理方法提供了一個新的思路.
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Zhou Shengyin , Zhou Lian , Chen Shaokai , Luo Jianjun
2006, 35(6):1006-1008.
Abstract:The effect of annealing process on the microstructure and magnetic properties of sintered NdFeB magnets were studied. The results show that the microstructure of magnets is ameliorated after annealing. The grain boundary became smoother and clearer, the Nd-rich phase distributed surrounding the grain dispersedly and equably, and the boundary phase became stable and well-proportioned. Therefore, the coercive force was remarkably enhanced, the residual magnetism and (BH) max were increased at the same time, and thermal stability of the magnet was improved enormously.
