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1、镓镓 基本信息物理化学特性银白色金属，在30时变为发光液体，冷却至0而不固化；在干燥空气中稳定，在潮湿空气中失去光泽，生成及少量氧化物；与碱反应放出氢气；能被冷浓盐酸浸蚀，对热硝酸钝性，高温时能与多数非金属反应；溶于酸和碱，微溶于汞，不溶于水；研究表明，镓在高温下对工程材料具有较强的腐蚀性，如300-400或更高温度下对不锈钢的腐蚀性；室温下的腐蚀性通常可以忽略； 低温下（30）可与铜缓慢发生反应，进而导致铜表面出现凹陷；实验验证，镓一般不与塑料（聚乙烯、聚丙烯、聚苯乙烯、PMMA）发生反应，即使温度升高至足以使上述塑料软化或熔化；镓不溶于水，因此经皮肤镓不容易被吸收；眼睛直接接触或吸入镓粉末
2、会导致疼痛；豚鼠皮下注入镓金属或合金导致骨疽； 对猫和鼠而言，胃对硫酸镓及硝酸钾的大剂量吸收会导致轻微中毒；人应尽量避免在三氧化二镓的环境下长期工作；一旦液态钾金属溅落至工作场所，如地板，先确认是否有导电可能，如果没有则立刻用冷水冲洗直至镓凝固，然后再做收集保存；为防止镓被人手的油污染，手套是必须的；6063 Aluminum-Alloy 5 hours of corrosion under 120C T2 Copper-AlloyAnodic Coloring 6063 Aluminum-Alloy1Cr18Ni9 Stainless Steel30 days at the temperat
3、ure of 60 0.5CCorrosion development between liquid gallium and four typicalmetal substratesTest object and conditionMorphology comparison of corrodedsurface of the 6063 Aluminum-Alloy (a) and of the T2 Copper-Alloy (b)Corrosion developments between the 6063 Aluminum-Alloy and liquid gallium: a no di
4、sturbance is exerted on gallium ball; b small disturbance is exerted on gallium ball.EDS analysis6063 Aluminum-AlloyT2 Copper-Alloy1Cr18Ni9 Stainless SteelAnodic Coloring 6063 Aluminum-AlloyConclusion6063 Aluminum-Alloy Liquid gallium has intense corrosion reaction with it, and the corrosion product
5、 is loose, promoting the infiltration of gallium into the corrosion product to form corrosion diffusion area with uniform gallium concentration. The corrosion product is also of low intensity.Thus, the 6063 Aluminum-Alloy cannot be used as the structure material for a liquid metal cooling system. T2
6、 copper Liquid gallium not only causes uniform corrosion process to the surface of it, but also has good compatibility with the corrosion layer and can form gallium covered area on the corroded surface. The corrosion resistance level of the T2 Copper-Alloy is between grade 6 and 7, which belongs to
7、a slightly high grade. But the T2 Copper-Alloy is inappropriate to be used as structural material of a liquid metal cooling system for the dynamic corrosion process will cause great damage to its surface.XAnodic Coloring 6063 Aluminum It has very strong corrosion resistance. However, in the flowing
8、liquid metal cooling system, the scouring effect that liquid metal of large density causes to the oxide layer on the surface must be considered.Meanwhile, the oxide layer cannot be scratched so as to avoid gallium infiltration. What is more, the system thermal resistance will increase because of the
9、 thin oxide layer. Thus, the Anodic Coloring 6063 Aluminum-Alloy can be used as structural material of a liquid metal cooling system only after certain good surface treatments. And the increased thermal resistance should be correctly evaluated for practical design of a liquid metal cooling system.1C
10、r18Ni9 Stainless Steel It shows integral corrosion resistance, high surface strength and strong resistance to scouring. The only shortcoming lies in its relativelylow thermal conductivity. Comprehensively considering the economy and practicality, the 1Cr18Ni9 stainless steel is the best structural m
11、aterial among the tested four specimens for a liquid metal cooling system. Corrosion resistance of structural materials to Ga2O at 1000 Test object and condition2 h20 hConclusionThe poor performance of Alloy 625 at 1000 C is consistent with its poor resistance to Ga at lower temperatures（400）；The po
12、or performance of Stellite 6 is likely associated with both the high solubility of Ga in Co, which is a primary component of this alloy, and with its high Cr content. Cr appears to play a significant role in corrosive attack of both these alloys by Ga2O. This selection of the Co-rich phase as the pr
13、eferred diffusion path for Ga penetration into Stellite 6 is consistent with the high diffusivity and solubility of Ga in Co.As for WCuNi alloy, Ga is seen to penetrate deeply beyond the reaction zone at the surface by means of the CuNi phase. This result is consistent with the penetration of Ga int
14、o Cu interphase regions. Cu and Ni appear to have diffused from the base metal to interact with Ga in creating the reaction zone at the sample surface.As for High-purity W, neither significant scale nor a reaction zone are observable at the surface of the sample.As for Silicon carbide, neither a sca
15、le nor a reaction zone are observed at the surface of the sample.Compatibility of ITER Candidate Materials with Static GalliumTest object and conditionType 316 SS（不锈钢）Inconel 625（铬镍铁合金 ）Nb-5 Mo-1 Zr alloyNickel 270 (99.995 wt.% Ni)Armco ironPure chromiumAt 300 and 400C for up to 3000 hConclusionCorr
16、osion rates for the alloys are lower than those for the pure metals；The iron-based Type 316 SS exhibit more corrosion than the nickel-based Inconel 625. At 400, the corrosion rate of Type 316 SS is nearly one order of magnitude greater than that of Inconel 625；Type 316 SS specimens exposed at 400C e
17、xhibited significant corrosion and formation of a thick, porous reaction layer. Although significant corrosion occurred, the specimens were not preferentially attacked along the grain boundaries. Exposure to gallium at 400C for extended test times (1000 h) led to separation of the specimen at the be
18、nd, resulting in accelerated corrosion at the sample ends. XRD analysis confirmed that the reaction layer on Type 316 SS consisted primarily of FeGa3 and gallium, with some CrGa4 in the region next to the steel surface. Inconel 625 specimens showed significant corrosion at 400C and little or no corr
19、osion at 300C. The Inconel 625 specimens exposed at 300C exhibited no reaction layer growth; however, the metal surface was etched by the liquid metal. At 400, metal loss and reaction layer growth was evident. Layer growth occurred evenly on the exposed surface, without inter-granular attack. There
20、was no distinction between attack of cold-worked and non cold-worked regions. The reaction layer contained CrGa4 and gallium across the entire thickness. XRD also identified the presence of the X phase observed in the Nickel 270 specimen. The Nb-5 Mo-l Zr alloy showed no measurable corrosion at 300
21、or 400C；The Nb-5 Mo-1 Zr alloy showed no measurable corrosion at 300 or 4OOC, although there appeared to be significant attack of the cold-worked region. The surface of the specimens after exposure was smooth, with very little formation of inter-metallic compoundAn -0.5-mm-thick iron specimen reacte
22、d completely within 24 h（400）；Armco iron exposed to gallium at 300C developed a very porous and thick reaction layer that was identified by X-ray diffraction (XRD) analysis as FeGa3, with gallium metal present in the pores.Similar corrosion behavior was observed for Nickel 270, in which the reaction
23、 layer primarily consisted of Ni2Ga3 and contained small amounts of NiGa4 in the region in contact with gallium.An 0.3-mm-thick chromium specimen disintegrated within 100 h（400）；A somewhat different behavior was observed for chromium metal; the specimen disintegrated into small crystals. analysis sh
24、owed the crystals to be CrGa4, indicating that the mechanism for corrosion of chromium is basically the same as that for nickel or iron. The difference is that the CrGa4, phase in equilibrium with the saturated solution of gallium did not adhere to the metal surface.The corrosion rates at 400 were e
25、stimated to be 10 and 2 m/h for Armco iron and Nickel 270, respectively；For chromium，the 100-h result yields a corrosion rate of 21.5 m/h（400）；）；The solubilities of iron, chromium, nickel, and niobium follow the sequence Ni Fe Cr Nb at temperatures above 300C, with the solubilities of iron, nickel,
26、and chromium greater by several orders of magnitude than that of niobium at any given temperature.At 400, corrosion rates were 4.0,0.5,and 0.03 mm/yr for Type 316 SS, Inconel 625, and Nb-5 Mo-1 Zr, respectively.镓的溶解度增大，抗腐蚀减弱ViscosityVapor Pressure(Purity)Vapor PressureVapor Pressure对比目前收集到得有限数据，此表数据与其他结果基本一致，且包含温度范围广，有较高的参考性，但对应的材料纯度等信息不明确。Wettability镓对大部分有机物、陶瓷及金属均有较好的润湿性THE END!Thank You!
