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应用于金矿开采业中的球阀在服役过程中由于受颗粒磨损,泥浆侵蚀,涂层粘结力/内聚力或者剪切力不高而发生破坏。修复价格昂贵耐腐蚀合金(CRA)球阀典型的工艺是:对合金基体进行钨极惰性气体保护焊(GTAW),球阀表面打磨,以及利用大气等离子喷涂(APS)技术在球阀表面制备陶瓷热喷涂涂层(TSC)。另一种修复方法是利用机加工使球尺寸减小,然后在陶瓷层下面沉积一层较厚的金属粘结层(MBC)以保证球阀的原始尺寸。本文研究了按照ASTM C633标准检测大气等离子喷涂陶瓷涂层的结合强度是否与超音速火焰喷涂的NiCrMo(哈氏合金)金属粘结层的厚度极限有关。实验所用的基体材料为三种耐腐蚀合金(CRA):钛G12,铬镍铁合金625以及2507双相不锈钢,在这三种基体表面沉积了8种不同厚度的金属粘结层。金属粘结层的厚度分别是:0.0015英寸,0.005英寸,0.015英寸,0.030英寸,0.045英寸,0.060英寸,0.075英寸以及0.090英寸。利用大气等离子喷涂工艺在上述8种不同厚度的金属粘结层表面喷涂厚度为0.015英寸的Cr_2O_3,Cr_2O_3-Al_2O_3和TiO_2这三种陶瓷涂层。对样品做了如下测试:涂层结合强度(ASTM C633)测试,金相显微组织分析(ASTM E1920),涂层孔隙率(ASTM E2109方法 B)测试。
Ball valves used in the gold mining industry suffer damage during service due to particle wear, mud erosion, coating adhesion / cohesion or low shear forces. Reworking costly CRA Ball Valves Typical processes are tungsten inert gas arc welding (GTAW) of alloy substrates, ball valve surface grinding, and the use of atmospheric plasma spray (APS) technology to prepare ceramic thermal spray coatings on ball valve surfaces Layer (TSC). Another repair method is to reduce the size of the ball by machining, and then deposit a thicker metal adhesive layer (MBC) under the ceramic layer to ensure the ball valve’s original size. This article examines whether the bonding strength of an atmospheric plasma sprayed ceramic coating to ASTM C633 standards is related to the thickness limit of a supersonic flame sprayed NiCrMo (Hastelloy) metal bonding layer. The base materials used in the experiment were three corrosion-resistant alloys (CRA): Titanium G12, Inconel 625, and Duplex 2507 stainless steel, and eight different thicknesses of metal adhesive were deposited on the three substrates. The thickness of the metal bonding layer is 0.0015 inches, 0.005 inches, 0.015 inches, 0.030 inches, 0.045 inches, 0.060 inches, 0.075 inches, and 0.090 inches, respectively. Three kinds of ceramic coatings, Cr2O3, Cr2O3-Al2O3 and TiO2, with a thickness of 0.015 "were sprayed on the surface of the above-mentioned 8 kinds of metal adhesive layers by the atmospheric plasma spraying process. The following tests were performed on the samples: coating bond strength (ASTM C633) test, metallographic microstructure analysis (ASTM E1920), and coating porosity (ASTM E2109 Method B) tests.