熱均壓參數與熱處理對CM247LC鎳基超合金熱均壓擴散接合件微組織及機械性質之影響

Microstructural evolution and mechanical properties of hot isostatic pressure bonded polycrystalline CM 247LC superalloy cast

郭妍伶(Yen-Ling Kuo)

指導教授 ： 王惠森

義守大學/理工學院/材料科學與工程學系/碩士(2014年)

https://doi.org/10.6343/ISU.2014.00244

摘要

為提升CM247LC鎳基超合金接合件之強度，本研究選用熱均壓(Hot isostatic pressing, HIP)擴散接合方式，配合特殊封罐設計及介面劑(interlayer)，進行不同熱均壓條件之固態擴散接合；熱均壓接合參數設計係透過高溫示差掃描量熱儀(differential scanning calorimetry, DSC)之熱性質分析並搭配參考文獻，及透過實驗結果設計出B、C二組改良式HIP擴散接合參數(1200℃/175MPa/4h；1220℃/175MPa/4h)。
然而在HIP製程後，易衍伸接合件降伏強度降低及延性下降等問題， 因此，本研究後續對HIP接合件進行後續熱處理 (1260℃/2h/1079℃/4h/871℃/20h)方式。並於實驗後透過光學顯微鏡(Optical microscope, OM)、掃描式電子顯微鏡(Scanning Electron Microscopy, SEM) 、X射線能量散怖分析(Energy Dispersive Spectrometer, EDS) 、電子反向散射衍射(EBSD) 、電子微探儀(EPMA)及拉伸測試(Tensile test)等方式藉以了解熱處理前、後與熱均壓參數對CM247LC熱均壓擴散接合件其微組織及機械性質之影響。
實驗結果顯示，參數C能結構緻密性高之接合介面，在室溫拉伸測試下，參數C達到973MPa的抗拉伸強度，其抗拉強度更甚於鑄件(920MPa)強度，為本研究最佳提供最佳之熱均壓參數。

關鍵字

CM247LC 超合金 ； 熱均壓擴散接合 ； 拉伸測試

並列摘要

To provide bonding pieces with the higher strength, in this study, CM247LC nickel based superalloy rods were joined using the hot-isostatic pressing (HIP) bonding technique with various bonding parameters, special design of canning process and interlayer. Based on the test results of Differential scanning calorimeter (DSC) analysis, references of literatures and initial experimental result, two proper HIP bonding conditions (Conditions B and C are 1200℃/175MPa/4h and 1220℃/175MPa/4h, respectively) were suggested.
To improve the yield and tensile strength of the HIP bonding pieces, the subsequent post HIP heat treatment (1260℃/2h/1079℃/4h/871℃/20h) was conducted. Then, heat treated boning pieces were investigated by using the optical microscopy (OM), scanning electron microscopy (SEM) equipped with energy dispersive spectrometer, EDS) and electron backscattered diffraction (EBSD), electron probe X-ray micro-Analysis (EPMA) and tensile test to study the effects of heat treatment process on the microstructure and mechanical properties of the HIP bonding pieces.
The test results have shown, under the HIP conditions C (the optimal conditions in the study), a sound HIP bonding piece was performed. The heat treated HIP　bonding pieces under condition C produced an excellent tensile strength (973MPa) which is even stronger than that (920MPa) of as-cast CM247LC.

並列關鍵字

CM247LC ； Nickel based superalloy ； Hot isostatic pressing (HIP) bonding ； Tensile test

參考文獻

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