Jiarong LI
,
Dingzhong TANG
,
Riling LAO
,
Shizhong LIU
,
Zhongtang WU
材料科学技术（英文）
The slabs of a single crystal superalloy were poured with 2.2% Re, 3.2% Re and 4.2% Re and other element contents of the alloys were basically kept no changed. The effects of Re on the ultimate tensile strength, creep rupture life and rafting of a single crystal superalloy were studied. The results showed that with increasing Re content the ultimate tensile strength decreased but the plasticity increased at 649℃, and the creep rupture life remarkably increased while the plasticity decreased at 982℃/248.2 MPa, 1038℃/206.8 MPa and 1070℃/176.8 MPa for the alloy; on the microstructure aspect, with increasing the creep rupture life of the alloy the rafting was getting bigger and bigger at the same test condition, and the rafting suppressed creep and increased creep rupture life in this single crystal superalloy.
关键词:
Jiarong LI
,
Shizhong LIU
,
Hailong YUAN
,
Zhengang ZHONG
材料科学技术（英文）
The three-dimensional solidification simulation of the investment castings of single crystal hollow turbine blade at the withdrawal rates of 2 mm/min, 4.5 mm/min and 7mm/min has been performed with the finite element thermal analysis. The calculated results are in accordance with the experimental ones. The results show that with the increase of withdrawal rate the concave curvature of the liquidus isotherm is larger and larger, and the temperature gradients of the blades increase. No effects of withdrawal rate on the distribution of the temperature gradients of the starter and helical grain selector of the blades are observed at withdrawal rates of 2 mm/min, 4.5 mm/min and 7 mm/min. The relatively high temperature gradient between 500ºC/cm and 1000 ºC/cm in the starter and helical grain selector is obtained at three withdrawal rates.
关键词:
Single crystal
,
null
,
null
Jiarong LI
,
Shizhong LIU
,
Zhengang ZHONG
材料科学技术（英文）
The three dimensional solidification simulation of the single crystal investment castings at withdrawal rates of 2 mm/min, 4.5 mm/min and 7 mm/min was performed with the finite element thermal analysis method. The calculated results were in accordance with the experimental ones. The results showed that with the increase of withdrawal rate the concave curvature of the liquidus isotherm was bigger and bigger and the temperature gradient of the castings decreased. No effects of withdrawal rate on the distribution of the temperature gradient of the starter and helical grain selector of the castings were observed at withdrawal rates of 2 mm/min, 4.5 mm/min and 7 mm/min. The relatively high temperature gradient between 500°C/cm and 1000°C/cm in the starter and helical grain selector was obtained at three withdrawal rates. The study indicates the three dimensional solidification simulation by finite element method is a powerful tool for understanding solidification and predicting defects in single crystal investment castings.
关键词:
Single crystal
,
null
,
null
