磷化处理对核主泵螺栓断裂行为的影响

Effect of Phosphating on Hydrogen Embrittlement of SA-540 B23 Steel for Nuclear Reactor Coolant Pump Bolt

采用SEM,氢含量分析仪和电化学充氢慢应变速率拉伸方法,研究了磷化处理及氢含量对核主泵用国产SA-540 B23主螺栓断裂行为的影响。结果表明,磷化处理对B23螺栓材料的断裂性能(慢应变速率拉伸及断裂韧性)没有影响。磷化处理后,H主要分布在磷化层中,而非基体内部。B23螺栓材料在电化学充氢环境下表现出明显的氢脆敏感性,断裂模式为沿晶开裂。

The effect of phosphating on the fracture behavior of a domestic SA-540 B23 steel used for nuclear reactor coolant pump bolt is studied by scanning electron microscope(SEM),hydrogen content analysis and in-situ hydrogen charging slow strain rate test(SSRT).The result shows that phosphating treatment has no effect on the fracture properties of B23 steel.Hydrogen content analysis shows that hydrogen is mainly distributed in the phosphate coating instead of the substrate.Hydrogen embrittlement tests show that B23 has obvious hydrogen embrittlement susceptibility under the attack of hydrogen,and the fracture feature is intergranular cracking.