高压输电导线的微动磨损行为研究

Research on Fretting Wear of High-voltage Transmission Conductor

在弯曲疲劳试验装置上对高压输电导线——LGJ150/25型钢芯铝绞线进行微动试验,轴向静载荷为30MPa,振动频率为10Hz,弯曲振幅为1mm。经5×106周次循环振动后,利用电镜扫描分析线夹处导线的微动磨损斑形貌特征。在磨损斑表面观察到大量磨屑,经分析其成分为氧化铝。根据磨损斑形貌的分布规律将导线的微动区域划分为微动粘着区、微动滑移区以及微动混合区。在微动粘着区的磨损斑有很大的塑性变形,磨损区有少量的裂纹产生。微动滑移区与微动混合区内磨损斑表面有片状剥离物存在,并且在剥离物周围有大量显微裂纹,裂纹长度较长。

LGJ150/25 high-voltage transmission conductor was tested on a conductor bending fatigue test system with an axial load of 30 MPa,a frequency of 10 Hz and a bending amplitude of 1 ram. The fretting spots surface of the conductor was analyzed by means of scanning electron microscope after being bent by 5 × 10^6 cycles. Plenty of abrasion bits are observed at the surface of abrasion spots, which is identified as Al2O3. According to the distribution of the abrasion spots, the fretting region of the tested conductor was divided into fretting adhesion, fretting slip and fretting mixing region. Abrasion spots have a big plastic deformation in fretting adhesion region. There are a few cracks on them. In the fretting slip and fretting mixing region, a mass of flakes peel off on the surface of abrasion spots. Plenty of cracks with a longer length are observed around the flakes.