ABSTRACT

The effect of Zr addition on the impact energy at −20°C, the microstructure, and inclusions of high-titanium low-alloy steels in the simulated heat-affected zone was investigated. The impact energy of the steel without Zr addition was 25.7 J and increased to 242.9 J for the steel with the addition of 80 ppm Zr. When the heat input was 300 kJ cm−1, the impact energy of the steel without Zr addition was 17.5 J and increased to 140.9 J for the steel with 80 ppm Zr, the nucleation potential of AFs increased from 24.4 /mm2 to 76.7 /mm⁻², and the average nucleation potential of inclusions decreased from 2.02 to 1.67. The grain refinement by the formation of acicular ferrites stemmed from the increase of 1–3 μm Al-Ti-Zr-O inclusions was responsible for the toughness improvement in CGHAZ of the Zr-bearing steel.

摘要

研究了Zr添加对高钛低合金钢模拟热影响区-20℃冲击功、显微组织和夹杂物的影响。未添加 Zr 的钢的冲击功为 25.7 J，添加 80 ppm Zr 的钢的冲击功增加至 242.9 J。当热输入为300 kJ cm−1时，未添加Zr的钢的冲击功为17.5 J，添加80 ppm Zr的钢的冲击功增加到140.9 J，AF的成核势从24.4 /mm2增加到76.7 /mm2 ^-2，夹杂物的平​​均成核势从2.02下降到1.67。1-3 μm Al-Ti-Zr-O 夹杂物的增加导致针状铁素体形成的晶粒细化，是含 Zr 钢 CGHAZ 韧性提高的原因。