案例研究结果分析
◉ 依据ASTM F2924-14,L-PBF Ti6Al4V的常规HIP工艺通过对打印过程中产生的典型缺陷致密化,可有效地使HCF强度达到600MPa(R=-1,N=106)。
◉ L-PBF Ti6Al4V在常规HIP温度895-955°C时的高温软化可以通过800°C/200MPa的低温HIP工来避免。这样材料的HCF强度可达750MPa(R=-1,N=107),并保持与高温去应力材料相同的屈服强度(Rp0.2 > 950MPa)。该工艺适用于尺寸小于300µm的缺陷。
◉ 为了致密1-2mm的大孔(这会发生在L-PBF高速构建时),并最大化屈服强度(Rp0.2 > 1000MPa),可将先进的高压热处理(HPHT = HIP+STA)成功应用于高性能AM零件。
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本文链接地址:Quintus高压热处理工艺可支持HIP和STA热处理同时进行,助力提高增材制造钛合金Ti6Al4V的疲劳强度(4)