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机械合金化过程中粉末变形与形成复合粉的工艺条件 总被引:1,自引:0,他引:1
本文将镍与钛单质混合粉在搅拌式高能球磨机中球磨。采用电子探针研究了粉末组织随球磨时间的变化。测定了了片状粉末的厚度以及复合粉分数随球磨时间的变化,并根据粉变形模型研究了球磨时形成复合粉所需时间与工艺条件的关系。 相似文献
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《材料导报》2016,(Z2)
在不同球磨时间条件下,采用机械球磨方法制备TiB_2-Ni(Al)复合粉末,其中Ni粉和Al粉的物质的量比为1∶1,TiB_2陶瓷相含量为40%(体积分数)。采用扫描电子显微镜(SEM)以及X射线衍射仪(XRD)分析球磨后粉末的显微组织结构及物相,研究不同球磨时间对制备TiB_2-Ni(Al)复合粉末物相演变、组织结构的影响。研究结果表明,随着球磨时间的延长,延性金属Ni和Al变形程度逐渐增大,粉末中呈现Ni/Al交替混合组织结构,此种结构有利于金属在球磨过程中扩散形成Ni(Al)固溶体,且逐渐细化的TiB_2相嵌入至金属Ni和Al颗粒中。通过物相分析发现,随着球磨时间的延长,Al衍射峰强度逐渐降低,并发现在球磨时间为36h时形成Ni(Al)固溶体。 相似文献
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为了获得具有良好微观组织的C-Cu复合粉末,以利于后续的压制、烧结和挤压等工艺,用机械球磨方法制备了3%C-Cu(质量分数)复合粉末.运用扫描电镜、背散射和X射线衍射等分析手段研究了该复合粉末的微观组织随球磨时间的演变规律.实验结果表明,随着机械球磨时间的增加,Cu颗粒由树枝状转变为层片状、块状,最后转变为近球形.球磨2 h,复合粉末中的石墨衍射峰消失.随着球磨的进行,复合粉末中Cu的微观应变逐渐增大.经3 h的机械球磨获得了晶粒尺寸约为20 nm的Cu纳米晶,说明该方法可以有效地细化晶粒组织. 相似文献
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以NiO粉和Al粉为原料,采用机械球磨诱发化学反应制备了Ni_2Al_3/Al_2O_3复合粉体。利用X射线衍射仪(XRD)和附带能量色散谱仪(EDS)的扫描电子显微镜(SEM)对复合粉体球磨过程中的固态反应过程、表面形貌进行表征。将Ni_2Al_3/Al_2O_3复合粉体用浓度为20%的NaOH溶液腐蚀2h,可得到纳米晶结构的Ni/Al_2O_3复合粉体。利用XRD和TEM对其物相和结构进行了表征。结果表明,球磨1h后混合粉末仍为NiO粉和Al粉,球磨3h后NiO粉和Al粉在机械力的作用下反应形成Ni_2Al_3和Al_2O_3粉体,机械力诱发的NiO和Al之间的反应属于突发型反应,继续球磨10h后形成Ni_2Al_3/Al_2O_3复合粉体。Ni_2Al_3/Al_2O_3复合粉体在70℃、质量比为20%NaOH溶液中刻蚀2h,可获得Ni/Al_2O_3复合粉体。 相似文献
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F. TehraniM.H. Abbasi M.A. Golozar M. Panjepour 《Materials Science and Engineering: A》2011,528(12):3961-3966
In this study, the effect of particle size of iron powder on α to γ transformation in the nanostructured high nitrogen Fe-18Cr-10Mn-4Mo stainless steel, produced by mechanical alloying (MA) was investigated. For this purpose iron powders with two different particle sizes were used. MA was performed under nitrogen atmosphere, using a high-energy planetary ball mill. X-ray diffraction (XRD) patterns and nitrogen analysis revealed that by decreasing the iron mean particle size, a higher transformation rate is obtained due to increase in the rate of nitrogen absorption. Moreover, nitrogen solubility in both milled samples was increased noticeably by increasing the milling time. This is believed to be due to the increase of lattice defects and development of nanostructure through MA. Variations of grain size and internal lattice strain versus milling time, for both iron particle sizes, showed that the critical ferrite grain size for austenite nucleation is less than 10 nm. 相似文献
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Nanocrystalline stainless steel powder was produced by ball milling of austenitic stainless steel scrap chips. The structural
and morphological changes of samples during ball milling and after subsequent heat treatment were investigated by X-ray diffractometery,
scanning electron microscopy and microhardness measurements. During ball milling the austenite in as-received chips partially
transformed to the martensite phase with nanoscale size grains of ∼15 nm. This structure exhibited high microhardness value
of about 850 Hv which is much higher than that for original samples. The deformation-induced martensite partially transformed
to austenite after annealing at 700 °C for 1 h reducing the hardness of powder particles. 相似文献
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利用阴极电弧离子镀技术在316L不锈钢基体上制备了CrN薄膜。采用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、纳米压痕仪对CrN薄膜的形貌、成分和力学性能进行了表征。为了研究Si_3N_4和52100钢对磨副材料对CrN薄膜和316L不锈钢干摩擦行为的影响,在2N、5N、8N三种载荷下,将CrN薄膜和316L不锈钢基体与Si_3N_4陶瓷球和52100钢球分别进行了往复式滑动干摩擦实验。采用扫描电子显微镜观察了磨痕的微观形貌,并对CrN薄膜和316L不锈钢基体的磨损机制进行了分析。结果表明:CrN薄膜表面平整,缺陷较少;CrN薄膜的纳米硬度约为28GPa,弹性模量约为350GPa;与Si_3N_4陶瓷球相比,CrN薄膜与52100钢球摩擦时摩擦因数相对较小(保持在0.7左右)且更加稳定;316L不锈钢的摩擦因数远大于CrN薄膜且波动较大;对磨球为Si_3N_4陶瓷球时,CrN薄膜的主要磨损机制为磨粒磨损,伴有少量的氧化和黏着磨损,316L不锈钢的磨损机制主要为磨粒磨损和塑性变形,伴有少量的氧化和黏着磨损;对磨球为52100钢球时,CrN薄膜的主要磨损机制为黏着磨损,伴有少量的氧化,316L不锈钢的磨损机制主要为黏着磨损,伴有少量的氧化和磨粒磨损。CrN薄膜与两种对磨球的磨损量均小于316L不锈钢基体的磨损量,说明CrN薄膜有效提高了基体的耐磨性。 相似文献
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One of the major sources of contamination during mechanical milling/alloying is from the surface erosion of the container
and the grinding medium. This can either be prevented by using grinding medium and container of same material of the milled
material or by adding a coating of the milled material on them. The paper describes the observations made during a mechano-chemical
reaction, being used for coating the balls and vials in a planetary ball mill. Visual observation, XRD, optical micrography
and EDS analysis were used to understand the progress of the reaction. Copper was successfully coated on the steel balls and
vials. The method can easily be adopted in daily production purposes, prior to mechanical milling of a Cu-based powder for
prevention of Fe contamination. 相似文献
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用高能机械球磨法制备了金属铁、钨微粉,对振动磨的结构及破碎原理作了简要介绍,分析了铁、钨粉末产品的粒度分布特性、比表面积变化情况,讨论了原料性质、球磨时间、球磨强度、球料比等因素对高能球磨过程的影响。 相似文献
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以类球形镍粉为原料,进行了湿法机械球磨制备片状镍粉的试验,考察了乙醇体积、球料比、球磨转速、球磨时间及助剂用量等因素对镍粉形貌的影响,采用XRD、SEM等对镍粉结构形貌进行了表征分析,确定了最佳工艺条件:乙醇体积60mL、球料比30:1、球磨转速450r/min、球磨时间3.5h、助剂A用量2%。在该条件下,得到的片状镍粉径厚比89,表面光滑平整,碎片粘附少,具有良好的金属光泽;其微观结构表明,球磨过程中,镍粉的微观内应力逐渐增加,晶粒不断细化;而且产品的片状化程度与<200>择优取向度有关。 相似文献
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Yuki Nakashima Hadi Razavi-Khosroshahi Chika Takai Masayoshi Fuji 《Advanced Powder Technology》2019,30(6):1160-1164
“Non-firing” ceramics have recently attracted much attention because many functional ceramics can be achieved by this method without the sintering process. The underlying idea of this method is to activate the surface of the particles by ball milling. In this study, the effect of adsorbed water on the surface of raw silica powder was investigated. Amorphous silica powder was mechanically treated by a rotating ball mill system and the surface activity of the raw and treated silica powders was measured based on the water adsorbed volume on the powder surface. The results showed that the surface activity of the silica powder increased with the increasing adsorbed water volume on the surface of the silica powder. In addition, better mechanical properties evaluated by the Vickers hardness test were achieved for the silica with more water adsorbed on its surface. The effect of milling energy and ball to powder ratio on activation of the silica was also investigated. 相似文献
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本文用60-100目的316L不锈钢粉末为原料,在不同轧制力的条件下,研究了轧制力与轧制不锈钢多孔板孔隙性能的关系,得出轧制力在90-100KN的范围内,可以获得孔隙性能均匀一致的轧制不锈钢多孔板。 相似文献