摘要
在煤矿产业中,27SiMn钢作为液压支架立柱和千斤顶的常用材料,最易受到损坏。采用激光熔覆JG-3合金粉末来改善其表面性能,增加其使用寿命。利用ANSYS有限元分析软件,对27组不同工艺条件下的激光熔覆温度场展开研究,得到激光熔覆某一时段熔池温度—时间曲线。经熔覆层半径理论对比以及单道熔覆试验验证,确定最优工艺参数组合为1000 W-8 mm/s-5 mm。在表面工程领域,适量添加稀土CeO_(2)可促使组织细化、提高显微硬度。为探究不同质量分数CeO_(2)对JG-3熔覆层组织及性能的影响,于27Si Mn钢表面进行激光熔覆JG-3和CeO_(2)试验,并进行显微组织观察、物相组成分析、显微硬度测试以及摩擦磨损试验。结果表明:添加1.0%CeO_(2)能显著改善组织均匀性和致密程度,有效减少气孔以及夹杂物的产生;促进Cr_(23)C_(6)相和Fe(Cr)固溶体形成,进而细化熔覆层组织结构,使熔覆层硬度分布均匀且达峰值,相比未添加时提高8%;其摩擦因数与摩擦质量损耗最小,具备最佳耐磨性能,对熔覆层耐磨性能的改善效果最为显著。
In the coal industry,27SiMn steel is widely used in key components,such as hydraulic support posts and jacks.However,frequent exposure to various stresses and wear in complex working environments render 27SiMn steel vulnerable.Therefore,to improve its surface properties and prolong its service life,the method of laser cladding JG-3 alloy powder was adopted.The temperature fields of 27 groups of laser claddings under different process conditions were studied using the ANSYS finite element analysis software,obtaining the temperature-time curve of a certain period of laser cladding.An increase in laser power,along with a decrease in spot diameter and scanning speed,led to an increase in temperature and range of the heat-affected zone in the laser cladding process.By comparing the melting state between the powders and simulation results with the theory of the cladding-layer radius,five groups of excellent parameters were determined,whereby the two groups with the smallest error were selected for the single-pass cladding test for verification.Comparing the simulation results of the melt pool,theoretical results of the melt pool,and actual results of the melt-pool test,the optimal combination of process parameters was determined to be 1000 W-8 mm/s-5 mm.In surface engineering,adding an appropriate amount of rare earth CeO_(2)has been demonstrated to be advantageous,promoting microstructural refinement and improving the microhardness and wear resistance of the material.In this study,laser cladding of JG-3 and CeO_(2)on a 27SiMn steel surface was tested,and the microstructure,phase composition,microhardness,and wear resistance of the coating were analyzed.The results showed that with an increase in CeO_(2)content,the uniform density and microhardness of the tissue first increased and then decreased,whereas the content of pores,inclusions,friction and wear coefficient,and wear amount first decreased and then increased.In summary,compared to that without CeO_(2),the microstructure with 0.5%content was more uniform;formation of pores and inclusions was reduced;microhardness was increased;and friction factor and wear amount were reduced.This indicates that 0.5%CeO_(2)improves the performance of the cladding layer.The addition of 1.0%CeO_(2)can significantly improve the uniformity and density of the tissue,effectively reducing the generation of pores and inclusions.Concurrently,it promotes the formation of the Cr23C phase and Fe(Cr)solid solutions,which further refine the microstructure of the cladding layer.The hardness distribution of 1.0%CeO_(2)cladding layer was more uniform and reached a peak value,which was 8%higher than that without CeO_(2).The friction factor and friction mass loss of the material were minimal,displaying the best wear resistance,and the improvement effect on the wear resistance of the cladding layer was the most significant.The higher the CeO_(2)content,the better the performance was.When the CeO_(2)content reached 1.5%and 2.0%with an increase in CeO_(2)content,the uniformity and density of the structure decreased;the porosity and inclusions increased;the microhardness decreased;and the friction coefficient and wear amount increased,which adversely affected the performance of the cladding layer.Thus,1.0%CeO_(2)had the best effect on the JG-3 alloy powder.In this study,laser cladding technology was combined with the addition of rare-earth CeO_(2)to improve the surface properties of 27SiMn steel.The effects of CeO_(2)on the microstructure and properties of the cladding layer were studied in detail,thereby providing a reference for the improvement of material properties in surface engineering.
作者
张喜峰
郭臣
王冬
张树秋
李小海
ZHANG Xifeng;GUO Chen;WANG Dong;ZHANG Shuqiu;LI Xiaohai(College of Mechanical Engineering,Jiamusi University,Jiamusi 154007,China;Hegang Sida Electromechanical Equipment Manufacturing Co.,Ltd.,Hegang 154103,China)
出处
《中国表面工程》
北大核心
2025年第3期173-184,共12页
China Surface Engineering
基金
中央引导地方科技发展资金(ZY23CG54)。
关键词
激光熔覆
温度场
稀土
显微硬度
摩擦磨损
laser cladding
temperature field
rare earth
microhardness
friction and wear
