In order to investigate the change in liquid microstructure of Al-Si alloytreated by electric pulse (EP), X-ray diffraction tests with liquid Al-Si alloy and ZL109 alloytreated or not by EP were carried out. The resul...In order to investigate the change in liquid microstructure of Al-Si alloytreated by electric pulse (EP), X-ray diffraction tests with liquid Al-Si alloy and ZL109 alloytreated or not by EP were carried out. The results show that the number of Al-Si atomic clustersdecreases and that of Al-Al and Si-Si atomic clusters increases for the treated samples. The testswith ZL109 alloy indicate that a large amount of primary crystal Si appears in the solidifiedmicrostructure after treated by EP. It is found that EP can change the microstructure of liquidmetal by affecting the probability of electrons appearing in different atoms (Al and Si) in theliquid metal. The combining force of different atoms decreases relatively, and that of the sameatoms increases, which is the main reason of reducing the atomic cluster with different atoms(Al-Si) and increasing the atomic cluster with the same atoms (Al-Al, Si-Si). The increasing of theatomic cluster with the same atom cluster resulted in the increasing of Si activity and the higherpoint of eutectics in the phase diagram. It makes a lot of primary silicon appeared in ZL109 alloy.展开更多
The effect of [S] on strength and toughness of low alloy steel plates inwhich sum of [P], [N], T[O] is less than 8x10^(-5) and the effect of T[O] on strength and toughnessof the steel plates in which sum of [S], [P], ...The effect of [S] on strength and toughness of low alloy steel plates inwhich sum of [P], [N], T[O] is less than 8x10^(-5) and the effect of T[O] on strength and toughnessof the steel plates in which sum of [S], [P], [N] is less than 7x10^(-5) were investigated. It isfound that the strength of the steel plates decreases with increasing [S] content when [S] is lessthan 4x10^(-5). When [S] varies within the range of 4x10^(-5)-1.2x10^(-4), [S] has no significanteffect on strength of the steel. The strength of the steel plates increases with increasing T[O]content when T[O] is less than 30x10^(-6), but decreases with increasing T[O] when T[O] is more than3x10^(-5). The difference between the LETT in plate length direction and LETT in width directiondecreases with decreasing [S] content. However, even when [S] is decreased to 9x10^(-6), thedifference of the LETT is still 16℃. When T[O] varies between 1.8x10^(-5) and 5.2x10^(-5), the lowtemperature impact toughness of the steel plates slowly decreases with T[O] increasing. When T[O]increases to more than 5.2x10^(-5), the low temperature toughness of the steel rapidly decreaseswith increasing T[O] content.展开更多
文摘In order to investigate the change in liquid microstructure of Al-Si alloytreated by electric pulse (EP), X-ray diffraction tests with liquid Al-Si alloy and ZL109 alloytreated or not by EP were carried out. The results show that the number of Al-Si atomic clustersdecreases and that of Al-Al and Si-Si atomic clusters increases for the treated samples. The testswith ZL109 alloy indicate that a large amount of primary crystal Si appears in the solidifiedmicrostructure after treated by EP. It is found that EP can change the microstructure of liquidmetal by affecting the probability of electrons appearing in different atoms (Al and Si) in theliquid metal. The combining force of different atoms decreases relatively, and that of the sameatoms increases, which is the main reason of reducing the atomic cluster with different atoms(Al-Si) and increasing the atomic cluster with the same atoms (Al-Al, Si-Si). The increasing of theatomic cluster with the same atom cluster resulted in the increasing of Si activity and the higherpoint of eutectics in the phase diagram. It makes a lot of primary silicon appeared in ZL109 alloy.
基金This research was supported by the State Key Fundamental Research Project (973 Project), (No. G199806150)
文摘The effect of [S] on strength and toughness of low alloy steel plates inwhich sum of [P], [N], T[O] is less than 8x10^(-5) and the effect of T[O] on strength and toughnessof the steel plates in which sum of [S], [P], [N] is less than 7x10^(-5) were investigated. It isfound that the strength of the steel plates decreases with increasing [S] content when [S] is lessthan 4x10^(-5). When [S] varies within the range of 4x10^(-5)-1.2x10^(-4), [S] has no significanteffect on strength of the steel. The strength of the steel plates increases with increasing T[O]content when T[O] is less than 30x10^(-6), but decreases with increasing T[O] when T[O] is more than3x10^(-5). The difference between the LETT in plate length direction and LETT in width directiondecreases with decreasing [S] content. However, even when [S] is decreased to 9x10^(-6), thedifference of the LETT is still 16℃. When T[O] varies between 1.8x10^(-5) and 5.2x10^(-5), the lowtemperature impact toughness of the steel plates slowly decreases with T[O] increasing. When T[O]increases to more than 5.2x10^(-5), the low temperature toughness of the steel rapidly decreaseswith increasing T[O] content.
