熔铸工艺条件对Mg-6Zn-0.5Y合金铸锭密度的影响

Effect of casting technology conditions on density of Mg-6Zn-0.5Y alloy ingot

试验研究了熔体温度、保温时间、冷却速度和C2Cl6除气剂添加量对Mg-6Zn-0.5Y合金铸锭密度的影响。结果表明:RPT(减压凝固法)铸锭密度随着熔体温度升高而降低,这表明氢含量随着温度的升高而增加;在相同的保温温度下,随着熔体保温时间延长,RPT铸锭密度逐渐降低,这表明氢含量随保温时间的延长而缓慢增加;在相同熔体温度下,随着熔体凝固冷却速度增加,铸锭密度逐渐增加;当熔体在720℃下分别添加占熔体质量的1%、3%和5%的C2Cl6除气剂处理时,铸锭的密度均比未处理的铸锭密度大,当C2Cl6用量为3%时,铸锭密度达到最大值,从1.8649 g/cm3增加到1.877 4 g/cm3,表明具有最佳的除氢效果。

The effects of melt temperature,holding time,cooling rate and C2Cl6 degassing agent on the density of Mg-6 Zn-0.5 Y alloy ingot were studied.The results show that the density of RPT(Reduced Pressure Testing method) ingot decreases with the increase of melt temperature,and the hydrogen content increases with the increase of temperature.With the increase of holding time,the density of RPT sample decreases gradually at the same holding temperature,and the hydrogen content increases slowly with the extension of holding time.With the increase of solidification cooling rate,the ingot density increases gradually at the same melt temperature.When the melt is treated with 1%,3% and 5% C2Cl6 degassing agent at 720 ℃,the density of ingot is higher than that of untreated ingot.When the content of C2Cl6 is 3%,the ingot density reaches the maximum value,increasing from 1.864 9 g/cm3 to 1.877 4 g/cm3,which has the best dehydrogenation effect.