案例研究結(jié)果分析

◉ 依據(jù)ASTM F2924-14，L-PBF Ti6Al4V的常規(guī)HIP工藝通過對打印過程中產(chǎn)生的典型缺陷致密化，可有效地使HCF強(qiáng)度達(dá)到600MPa（R=-1，N=106）。

◉ L-PBF Ti6Al4V在常規(guī)HIP溫度895-955°C時(shí)的高溫軟化可以通過800°C/200MPa的低溫HIP工來避免。這樣材料的HCF強(qiáng)度可達(dá)750MPa（R=-1，N=107），并保持與高溫去應(yīng)力材料相同的屈服強(qiáng)度（Rp0.2 > 950MPa）。該工藝適用于尺寸小于300µm的缺陷。

◉ 為了致密1-2mm的大孔（這會(huì)發(fā)生在L-PBF高速構(gòu)建時(shí)），并最大化屈服強(qiáng)度（Rp0.2 > 1000MPa），可將先進(jìn)的高壓熱處理（HPHT = HIP+STA）成功應(yīng)用于高性能AM零件。

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