目的:本文描述了在LM25铝合金中使用石墨(Gr)和碳化硼(B4C)作为多种纳米颗粒增强材料。因为碳化硼自然吸收中子辐射,用碳化硼金属基复合材料增强的铝合金在核屏蔽应用中获得了兴趣。努力的主要目标是创造具有高耐磨性的复合材料,显微硬度高,和用于核应用的高极限抗拉强度。
背景:科学技术给人类生活带来了巨大的变化。通过在开发新的和创新技术中使用创新,人类的负担已被最小化。为了提高人类的生活质量,新鲜,轻量级,创意材料正在被使用,它在科学技术中起着至关重要的作用,减少了人类的工作量。正在使用由金属制成的复合材料,因为它们重量轻。中子吸收,高极限强度,高耐磨性,显微硬度高,高导热性和导电性,高真空环境电阻,在静态和动态条件下的低热膨胀系数都是核应用中使用的混合金属基复合材料的要求。
目的:•搅拌铸造用于制造新型LM25铝合金/石墨和碳化硼杂化纳米复合材料。•机械性能,如极限拉伸强度,屈服强度,伸长率,显微硬度,并计算磨损行为。•进行了三项分析:微观结构,磨损表面分析,拉伸试样的断口分析。
方法:•搅拌铸造工艺<•拉伸,硬度,磨损试验•材料表征-FESEM,光学显微镜,EDS<结果:机械性能值为308.76MPa,293.51MPa,7.8,169.2VHN,和0.01854mm3/m的极限抗拉强度,屈服强度,伸长率,显微硬度,和磨损行为,分别。这意味着合成的复合材料可以成功地用于核应用。
结论:从本研究工作中得出随后的解释:•通过采用搅拌铸造技术成功地制造了LM25/B4C/Gr杂化纳米复合材料。对于核屏蔽应用,这些复合材料是用三种不同重量百分比的纳米颗粒增强材料在2,4,6%碳化硼和恒定的4wt。%石墨。•三混合纳米复合材料制造的铸件的显微硬度值被确定为143.4VHN,156.7VHN,和169.2VHN,分别。•混合纳米复合材料的微观结构表明,底层LM25铝合金基体的细晶,存在均匀分散的石墨和碳化硼纳米颗粒。
•进行了微拉伸试验,发现极限拉伸强度,屈服强度和伸长率值为281.35MPa,296.52MPa,308.76MPa,分别为269.43、274.69、293.51和3.4、5.7、7.8。
•变形导致混合LM25/B4C/Gr纳米复合材料在延性模式下断裂。由于纳米颗粒的增强和基体的紧密连接,裂缝中出现了凹陷和空洞。
•基于输入参数施加载荷的纳米复合材料的磨损损失,滑动速度和滑动距离值为0.02456、0.02189、0.01854、0.02892、0.02586、0.02315和0.02682、0.02254、0.02015mm3/m,分别。
•LM25合金的元素分析显示铝合金相为最大峰,其余元素为较小峰;光谱分析揭示了硼(B)的存在,石墨(C),硅,和黑色的铝合金LM25。
•通过磨损表面FESEM调查,结果表明,在滑动和高负荷情况下,碎片,分层,和凹槽发展。进一步破裂,好,当将低应力和滑动情况应用于LM25/B4C/Gr和搅拌铸造试样时,可以看到连续的凹槽。该结果暗示存在轻度粘合和分层磨损过程。。
OBJECTIVE: This article describes the use of graphite(Gr) and boron carbide (B4C) as multiple nanoparticle reinforcements in LM25 aluminum alloy. Because boron carbide naturally absorbs neutron radiation, aluminium alloy reinforced with boron carbide metal matrix composite has gained interest in nuclear shielding applications. The primary goal of the endeavor is to create composite materials with high wear resistance, high microhardness, and high ultimate tensile strength for use in nuclear applications.
BACKGROUND: Science and Technology have brought a vast change to human life. The human burden has been minimized by the use of innovation in developing new and innovative technologies. To improve the quality of human life, fresh, lightweight, and creative materials are being used, which play a vital role in science and technology and reduce the human workload. Composite materials made of metal are being used because they are lightweight. Neutron absorption, high ultimate strength, high wear resistance, high microhardness, high thermal and electrical conductivity, high vacuum environmental resistance, and low coefficient of thermal expansion under static and dynamic conditions are all demands for the hybrid metal matrix composites utilized in nuclear applications.
OBJECTIVE: • Stir casting is used to create the novel LM 25 aluminum alloy/graphite and boron carbide hybrid nanocomposites. • The mechanical properties such as ultimate tensile strength, yield strength, percentage of elongation, microhardness, and wear behavior are calculated. • Three analyses are performed: microstructure, worn surface analysis, and fracture analysis of the tensile specimen.
METHODS: • Stir casting process< • Tensile, Hardness, Wear Test • Materials Characterization - FESEM, Optical Microscopy,
EDS< Results: The mechanical properties values are 308.76 MPa, 293.51 MPa, 7.8, 169.2 VHN, and 0.01854mm3/m intended for ultimate tensile strength, yield strength, percentage of elongation, microhardness, and wear behavior, respectively. This implies that the synthesized composite may be used in nuclear applications successfully.
CONCLUSIONS: The subsequent explanation was drawn from this investigative work: • The LM 25/B4C/Gr hybrid nanocomposite was successfully manufactured by employing the stir casting technique. For nuclear shielding applications, these composites were prepared with three different weight percentages of nanoparticle reinforcements in 2,4,6% Boron carbide and constant 4 wt.% graphite. • The microhardness values of the three-hybrid nanocomposite fabricated castings were determined to be 143.4VHN, 156.7VHN, and 169.2VHN, respectively. • The hybrid nano composite\'s microstructure revealed that the underlying LM 25 aluminum alloy matrix\'s finegrained, evenly dispersed nanoparticles of graphite and boron carbide were present.
• The microtensile test was carried out and it was found that the ultimate tensile strength, yield strength and percentage of elongation values are 281.35MPa, 296.52MPa, 308.76MPa, 269.43, 274.69, 293.51 and 3.4, 5.7, 7.8 respectively.
• Deformation caused the hybrid LM 25/B4C/Gr nanocomposite to fracture in ductile mode. Dimples and cavities are seen in the fracture because of the nanoparticle reinforcements and the matrix\'s tight connection.
• The wear loss of nanocomposite based on the input parameter applied load, sliding velocity and sliding distance values are 0.02456, 0.02189, 0.01854, 0.02892, 0.02586, 0.02315 and 0.02682, 0.02254, 0.02015 mm3/m, respectively.
• The LM 25 alloy\'s elemental analysis displays the aluminum alloy phase as the largest peak and the remaining elements as smaller peaks; also, the spectral analysis reveals the presence of boron (B), graphite (C), silicon, and ferrous in the aluminum alloy LM 25.
• Through worn surface FESEM investigation, it was shown that under sliding and high load situations, debris, delamination, and groove develop. Further rupture, fine, and continuous grooves were seen when low stress and sliding circumstances were applied to the LM 25/B4C/Gr and stir cast specimen. This result implies the presence of mild adhesive and delamination wear processes..