Abstract: The TOPSIS method was improved by information entropy weights as attribute weights， failure modes of aeroengine life-limited parts were taken as assessment objects， and risk indicators were blurred.This new method for risk assessment of life-limited parts was proposed.Three factors with severity， occurrence and detection difficulty of failure mode were made to be main risk indicators.Triangular fuzzy number decision matrix was established and standardized.In the case of fault data for small sample， decision information of relevant experts and engineers was integrated to calculate entropy weights of risk indicators， and then the entropy weights were used as weighted vectors to amend the normative decision matrix.The TOPSIS was utilized to evaluate.Five failure modes were evaluated with positive and negative ideal solutions， Euclidean distances and relative proximity data.The fuzzy risk assessment method based on improved entropy TOPSIS may achieve the accurate sorting of assessment objects， and it is more efficient to analyze than the hazard matrix mapping method.The method may provide a reliable basis for risk reduction and development of preventive measures in failure mode and effect analysis（FMEA） method.

Key words: entropy, technique for order preference by similarity to ideal solution （TOPSIS）, life-limited part, fuzzy, risk assessment

摘要： 以航空发动机限寿件典型故障模式为评估对象，将风险指标模糊化，并以信息熵权作为属性权重，对逼近理想解排序（TOPSIS）方法进行改进，提出一种新的限寿件风险评估方法。以故障模式的严重度、发生频度和被检测难易度这3个参数为主要风险指标，建立三角模糊数决策矩阵，并进行规范化处理；在限寿件故障数据为小子样的情况下，运用熵权法，集成相关专家和工程人员的决策信息计算风险指标的熵权，并作为加权向量对规范决策矩阵进行修正；利用TOPSIS法进行评估。应用实例分析与计算，用正负理想解、欧氏距离和相对接近度等数据对5种故障模式进行模糊风险评估。结果表明，改进熵权TOPSIS的模糊风险评估方法可以实现评估对象的精确排序，比危害性矩阵作图法分析效率更高，能够为故障模式影响分析（FMEA）方法中制定预防措施和降低风险提供可靠依据。

关键词: 熵权, 逼近理想解排序, 限寿件, 模糊, 风险评估