护栏板开裂问题分析与解决

Analysis and solution of guardrail plate cracking problem

在采用Q235B热轧带钢生产波形防撞护栏板过程中,护栏板端部经常发生开裂问题。通过对护栏板的化学成分、气体含量、显微组织、断口形貌等进行观察后,认为热轧带钢中严重的非金属夹杂物破坏了带钢的横向力学性能,导致护栏板端部在剪切时加工硬化的作用下发生开裂。通过改善Al脱氧效果、增加软吹时间以及提高卷取温度等措施,提高了热轧带钢横向弯曲性能,降低了其加工硬化的影响,有效解决了由于非金属夹杂物导致的护栏板端部开裂问题。

During the process of producing corrugated anti-collision guardrail plate with hot rolled strip,cracking problem often occurs at the end of guardrail plate.After observing the chemical composition,gas content,microstructure and fracture morphology of the guardrail plate,it is considered that serious non-metallic inclusions in hot rolled strip destroy the transverse mechanical properties of the strip,leading to cracking of the end of the guardrail plate under the action of machining hardening during shearing.By improving the deoxidize effect of Al,increasing the soft blowing time and increasing the coiling temperature other measures,increased the hot rolled strip transverse bending property,reduced impact of work hardening,and the crack problem of guardrail plate end caused by non-metallic inclusions was effectively solved.