文章信息/Info

Title:

Microstructure Evolution and Mechanical Behavior Study of SiCf/SiC Composite Materials under High Temperature Media

文章編號:

1674-3962(2025)02-0146-08

作者:

楊晨曦; 曹偉; 黃寶慶; 原紅星; 胡江波; 廉鐵江; 王明珠

中國航發動力股份有限公司，陜西 西安 710003

Author(s):

YANG Chenxi;  CAO Wei;  HUANG Baoqing;  YUAN Hongxing;  HU Jiangbo;  LIAN Tiejiang;  WANG Mingzhu

AECC Aviation Power Co., Ltd., Xi’an 710003, China

關鍵詞:

SiCf/SiC復合材料;  微觀結構;  高溫;  氬氣介質;  空氣氧化介質;  拉伸性能

Keywords:

SiCf/SiC composite materials;  microstructure;  high temperature;  argon media;  air media;  tensile properties

分類號:

V254.2

DOI:

10.7502/j.issn.1674-3962.202412005

文獻標志碼:

A

摘要:

對具有PyC/(SiC)4多層界面相的SiCf/SiC復合材料在1050和1350 ℃氬氣介質和空氣氧化介質中分別進行0.25，1，4和16 h熱處理，分析不同高溫介質環境下SiCf/SiC復合材料微觀結構演變及與力學性能的關系。結果表明：高溫氬氣介質下暴露后的復合材料微觀結構無變化，而隨著熱處理時間與溫度的增加，由于纖維和基體受到熱損傷，導致材料的拉伸強度呈下降趨勢，但仍保持韌性特征。在高溫空氣氧化介質下，經高溫短時氧化后，復合材料中的PyC界面被氧化消耗，在纖維與SiC界面相之間形成環形孔隙；經高溫長時間氧化后，環形孔隙將被SiO2填充。上述微觀結構的變化使SiCf/SiC復合材料拉伸斷口形貌呈現3種類型，即含有PyC界面的復合材料具有適中的纖維拔出長度，無PyC界面的復合材料具有較長的纖維拔出長度，以及形成SiO2層的復合材料無纖維拔出。經高溫空氣氧化介質處理后的SiCf/SiC復合材料拉伸強度整體低于經氬氣介質熱處理后的，主要原因是纖維與基體受到氧化損傷，同時SiO2在界面生成，使得材料失去韌性。

Abstract:

In this study, SiCf/SiC composite materials with PyC/(SiC)4 multilayer interfacial phase were subjected to thermal treatments at 1050 and 1350 ℃ in argon and air media for durations of 0.25, 1, 4 and 16 h. The microstructural evolution and the relationship with mechanical properties after different high-temperature media thermal treatments were analyzed. The results showed that there was no change in the microstructure of the composite material after exposure to high-temperature argon media. However, with the increasing in treatment time and temperature, the tensile strength of the material decreased due to thermal damage of the fibers and matrix, while the composite still maintained the toughness characteristics. In the air media, after short-term oxidation at high temperatures, oxidation loss occurred at the PyC interface of the composite material, resulting in annular voids between fibers and SiC interfacial phases. After long-term oxidation at high temperatures, these annular voids were filled with SiO2. These changes in microstructure resulted in three main tensile fracture morphologies for SiCf/SiC composites: materials contained PyC interfaces had moderate fiber pull-out lengths, materials without PyC interfaces had longer fiber pull-out lengths, while materials with a layer of SiO2 had no fiber pull-out observed. The overall tensile strength of SiCf/SiC composites treated in high-temperature air media was lower than that treated with argon media, mainly due to oxidative damage to fibers and matrix and loss of toughness caused by formation of SiO2 at interfaces.