摘要：
The coatings are fabricated using austenitic stainless steel powder with various contents of carbon and boron via laser remanufacturing technique. A new synchronous lateral powder feeding device is adopted to avoid surface oxidation of molten pool. The authors find that the strength can be increased but plasticity is decreased of with the rise of boron content due to the formation of lamellar borides phase structures, which are very brittle and have high hardness. In addition, the authors also find that the tensile strength and hardness are enhanced by increasing the content of carbon, while the plasticity is deteriorated due to the formed carbide in the grain of the austenitic stainless steel coating. The coatings of austenitic stainless steel powder with various contents of carbon and boron are fabricated using laser remanufacturing technique. A new synchronous lateral powder feeding device is adopted to avoid surface oxidation of molten pool. The tensile strength and hardness are enhanced by increasing the content of carbon and boron, while the plasticity is deteriorated.
通讯机构：
School of Mechanical Engineering, University of South China, Hengyang, Hunan, China
关键词：
激光技术;激光熔覆;马氏体/铁素体双相不锈钢;微量硼元素;显微组织;高性能
摘要：
为了获得高强度、高韧性、耐蚀性好的铁基合金涂层,在Q235基体上激光熔覆了含微量硼元素的低碳、低合金马氏体/铁素体双相不锈钢(M/Fss)合金粉末。研究结果表明,所制备的激光熔覆层表面具有金属光泽,内部无夹杂、气孔等缺陷。熔覆层由马氏体、铁素体、主要沿枝晶间呈均匀不连续分布的硼碳化物M(B,C)和少量在枝晶内析出的M23(B,C)6组成(M为Fe、Cr等)。熔覆层力学性能优异,平均显微硬度为431.9 HV,抗拉强度为1352 MPa,延伸率为12.3%,且耐腐蚀性能优于1Cr13马氏体不锈钢。这一新型的M/Fss涂层可广泛应用于同时对力学性能和耐蚀性能要求高的工作环境下的铁基材料表面改性或再制造。 This study aims to obtain a Fe-based alloy coating with high strength, high toughness, and good corrosion resistance. Therefore, a novel low-carbon and low-alloy martensite/ferrite dual-phase stainless steel (M/Fss) powder with trace addition of boron is cladded on Q235 steel by the laser cladding technique. The research results reveal that the surface of the laser cladding coating has metallic luster, and there are no inclusions and pores in the coating. The coating is constituted of martensite, ferrite, and boron carbides M(B,C) with uniform and discontinuous distribution along the dendrite (M represents Fe, Cr, etc.). A few M23(B,C)6 particles precipitated within the dendrite. The cladding layer exhibits excellent mechanical properties, including average hardness of 431.9 HV, tensile strength of 1352 MPa, and ductility of 12.3%. Its superior corrosion resistance is better than that of 1Cr13 martensite stainless steel. This new type of M/Fss coating can be widely used for surface modification or remanufacturing of Fe-based materials in working environments requiring mechanical and corrosion resistances.
摘要：
Vending machine as one kind of non-store business has been very popular in the developed countries for many years, and so has been China. Unfortunately, there are only very few related researches that have been done for studying consumers how they operate a vending machine by an efficient and convenient way. The main goal of this research is to explore how to apply the wireless location technology and route planning on designing the display panel of the removable vending machine.
关键词：
Hastelloy-N alloy;Laser cladding;AlN coating;Corrosion resistance;LiF-KF-NaF molten salt
摘要：
High-temperature corrosion resistance is a big issue for structural materials in molten salt reactors. A simple but effective laser cladding technique has been utilized for producing a compact AlN coating on Hastelloy-N alloy. The results show that the laser-cladded AlN coating improves the compatibility of Hastelloy-N alloy in LiF-NaF-KF molten salt at 900 degrees C significantly. The uncoated Hastelloy-N alloy is composed of gamma-Ni and M6C phases, showing a typical intergranular corrosion with a precipitation of new Cr9Mo25Ni20 phase after corrosion. In contrast, the AlN coating exhibits a silghtly unifrom corrosion and protects the Hastelloy-N substrate effectively. The laser-cladded specimes are composed of gamma-Ni and AlN before and after corrosion. The possible reasons for the discrepancy in the corrosion behavior between uncoated and coated specimens are discussed in this job.
作者机构：
[张曼莉; 邱长军; 蒋艳林; 郑文权; 夏琰] School of Mechanical Engineering, University of South China, Hengyang;Hunan;421001, China;[张曼莉; 邱长军; 蒋艳林; 郑文权; 夏琰] Hunan;[张曼莉; 邱长军; 蒋艳林; 郑文权; 夏琰] 421001, China
通讯机构：
[Qiu, C.-J.] S;School of Mechanical Engineering, University of South China, Hengyang, Hunan, China
摘要：
目的通过在Cr膜中添加Sn Al元素及中温液相烧结,提高锆合金膜基界面结合强度。方法在Cr靶中添加SnAl元素,制备一种均匀分布的Cr Sn Al合金靶材（原子比Cr:Sn:Al=95:4:1）,并利用直流磁控溅射（DCMS）技术在锆合金表面制备约5μm厚的Cr SnAl膜层,再将CrSnAl膜层试样放入Ar保护气氛炉中进行中温烧结（温度为600℃,时间为30 min）,随炉冷却至室温。利用XRD、SEM、EDS及体式显微镜分析中温烧结对Cr Sn Al膜层形貌、组织结构及元素扩散的影响;根据涂层弯曲断裂形貌、切削划痕力和切屑形貌综合评价膜基界面结合强度。结果添加SnAl后,Cr膜层表面孔隙等缺陷明显减少,膜基界面结合强度得到较大提升,从41.7 MPa提升到了45.8 MPa。600℃烧结后,Cr SnAl膜层韧性增强,并出现韧窝形貌,剪切唇仅为烧结前CrSnAl膜层的1/2,Cr Sn Al/Zr界面结合强度进一步提升到52.1 MPa。结论 Cr膜中添加SnAl有利于膜基界面元素扩散,对膜基界面结合强度提高有较大影响;中温烧结Cr Sn Al膜层韧性及膜基界面结合强度均有较大提升,进而改善了膜基界面结合性能。
作者机构：
[邱长军; 陈勇; 胡良斌; 黄鹤] School of Mechanical Engineering, University of South China, Hengyang, Hunan, 421001, China;[李怀林; 刘艳红] State Power Investment Corporation Central Research Institute, Beijing, 102209, China
摘要：
China low activation martensitic (CLAM) steel is the preferred candidate structural material for the Chinese international thermonuclear experimental reactor test blanket module (ITER TBM). Surface coating technology is often adopted to alter or improve the performance of materials. In CLAM steel, surface treatment plays a key role in rendering them appropriate for application in accelerator driven sub-critical system (ADS). Here, the authors prepare multiphase ceramic coatings on CLAM steel via laser in-situ reaction technology. The prepared multiphase ceramic coatings exhibit optimal corrosion resistance. The liquid lead-bismuth eutectic (LEB) corrosion resistance can be attributed to inferior wettability of interface between the LEB and multiphase ceramic coatings, faint shear force produced by LEB, and stable chemical and physical property of the coatings. Moreover, the irradiated specimens also display excellent corrosion resistance against helium ions irradiation. The CLAM steel is found to suffer significant corrosion in the flowing LEB. Such multiphase ceramic coatings as a protective layer on the ADS candidate structural materials CLAM steel surface exhibit the strongest LEB corrosion resistance, which can be applied to handle nuclear waste under extreme conditions.
