冷拔油缸管失效原因分析及探討

Analysis of Reason for Cracking of Cold-drawn Hydraulic Cylinder Pipe

摘要: 采用冷拔+刮滾工藝生產(chǎn)的45鋼成品油缸管，使用11 h后，在20 MPa左右的壓力下發(fā)生貫穿性開裂。研究開裂斷口形貌、腐蝕產(chǎn)物成分、力學(xué)性能、微觀組織等，分析該油缸管的開裂原因。分析認(rèn)為：受去應(yīng)力退火溫度偏低、網(wǎng)狀鐵素體組織等綜合因素的影響，45鋼油缸管的塑性和韌性下降、脆性增加，導(dǎo)致其耐壓性能下降，從而造成開裂。

Abstract: Addressing the fact that the finished 45 steel hydraulic cylinder pipe as made with the process of colddrawing plus scraping-rolling develops through-cracking after being used for 11 hours under about 20 MPa pressure, the reason for the said cracking is analyzed by means of studying such aspects as fracture morphology, composition of the corrosive product, mechanical property and microstructure, etc.It is regarded via the analysis that affected by such comprehensive factors as rather low temperature for stress-relief annealing process and reticular ferrite microstructure, etc., both the plasticity and toughness of the 45 steel hydraulic cylinder pipe are reduced, whereas its brittleness is increased, which leads to reduction of the pressure resistance as resulting in the said cracking.