A new α preformation factor formula was proposed in the framework of unified fission model (UFM), the coefficients of the formula were obtained by fitting the extracted α preformation factors of 465 nuclei with $Z=62-103$. The root mean square (RMS) deviation of the calculated α preformation factors with the extracted values is 0.388, indicating that the formula can describe the α particle preformation probability reliably. Then the α decay half-lives for recently observed 76 superheavy nuclei (SHN) are calculated by the UFM with the new α preformation factor formula. The comparison between the calculated values and the experimental data demonstrates that the UFM taking the preformation factor into account is a useful tool to investigate the α decay half-lives of SHN. Encouraged by this, the predictions of α decay half-lives for SHN $Z=119,120$ isotopes are made by using the theoretical mass tables FRDM2012, WS4 and WS2016+RBFs to determine the $Q_{\alpha }$ values. The predictions can provide references for experiments of synthesizing new SHN if the mass tables are accurate enough.

在统一裂变模型（UFM）的框架内提出了一个新的α预形成因子公式，该公式的系数是通过将提取的465个原子核的α预形成因子与$Z=62-103$. 计算得到的α预形成因子与提取值的均方根偏差为0.388，表明该公式能够可靠地描述α粒子预形成概率。然后，UFM 使用新的α预形成因子公式计算最近观察到的 76 个超重核 (SHN)的α衰变半衰期。计算值与实验数据之间的比较表明，考虑预形成因子的 UFM 是研究SHN α衰变半衰期的有用工具。受此鼓舞，SHN的α衰变半衰期预测$Z=119,120$ 同位素是通过使用理论质量表 FRDM2012、WS4 和 WS2016+RBFs 来确定的 ${问}_{\alpha }$值。如果质量表足够准确，该预测可为合成新的SHN的实验提供参考。