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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