等离子喷涂Al_2O_3陶瓷涂层的冲蚀磨损特性

研究了在固体颗粒冲蚀条件下 ,不同冲击速度、不同磨料尺寸等因素对等离子喷涂Al2 O3陶瓷涂层冲蚀磨损率的影响 ,并在不同条件下与 2 0号钢进行了对比试验 ,分析了等离子喷涂Al2 O3陶瓷涂层的冲蚀磨损特性及磨损机理 ,提出等离子喷涂Al2 O3陶瓷涂层具有脆性特征的冲蚀磨损特性 。

铁粉颗粒对TP347H不锈钢的冲蚀磨损特性研究

TP347H不锈钢常作为石油化工行业中的管道材料,在油气输送过程中,输送介质往往夹杂着固体颗粒,将造成管道内壁面发生磨损而破坏。考虑不同冲击角度、颗粒速度、颗粒质量流量及粒径等因素,基于冲蚀实验对Finnie冲蚀模型进行修正,探究铁粉颗粒对TP347H不锈钢的冲蚀磨损特性。研究表明:冲蚀实验中,冲蚀率随颗粒速度、颗粒质量流量的增加而增加,且颗粒速度、颗粒质量流量与冲蚀率遵循三次函数关系;当颗粒冲击角度为45°时,冲蚀率最大,颗粒冲击角度与冲蚀率呈指数函数关系;在指数n=2,模型常数k=1.272×10^(-6)修正条件下,采用DPM模型计算得到的冲蚀率与实验值的最大误差为10%,符合工程应用要求。修正后的Finnie冲蚀模型为TP347H不锈钢的冲蚀磨损特性研究提供了理论指导。

含砂天然气管道弯管冲蚀磨损特性研究

当天然气管道中混有砂粒时,弯管易受冲蚀而使其壁厚减薄。为此,以国内某含砂气田输气首站内的工艺管道为例,采用Fluent软件对弯管的冲蚀磨损特性进行了数值模拟研究。结果表明:在正常输气工况下,弯管外拱的下部为其冲蚀磨损集中区,且最大局部减薄量为0.4 mm/a。另外,弯径比的增大会扩大弯管的冲蚀磨损集中区范围,同时使其最大冲蚀磨损速率减小;内径的增大不会改变弯管的冲蚀磨损集中区分布,但会造成其最大冲蚀磨损速率减小。研究结果可为后续进一步研究弯管的冲蚀磨损防护措施提供参考。

Erosion wear experiments and simulation analysis on bionic anti-erosion sample

The dorsal surface of a desert lizard has excellent particle erosion resistance.In this paper,a bio-inspired sample was designed and fabricated based on the biological characteristics of the dorsal skin of the desert lizard(Laudakin stoliczkana).The bionic sample consists of two materials with different characteristics,which form a two-layer composite structure.The particle erosion property and erosion wear mechanism of the bionic sample was studied by means of sandblast experiment and numerical simulation,respectively.The experimental results show that,in the stage with steady abrasion rate,the weight loss per unit time of the bionic sample is about 10%lesser than the control sample.The numerical simulation indicated that the two-layer structure of the bionic sample can efficiently absorb the normal stress,and dissipate the stress in the horizontal direction.Thus,the stress concentration on the sample surface is suppressed.The two-layer structure is contributed to the decentralizing of the stress distribution,and thus the occurrence probability of erosion damage can be decreased.