摘要:本文采用比容差法研究铝合金在不同热处理工艺下体积的变化,并用热膨胀试验对其进行实验验证。之后,使用XRD对不同热处理后的试样进行了残余应力的测量,从铝合金体积变化的角度,分析残余应力的变化规律。结果表明:比容差法可较为准确的称量出不同热处理工艺后铝合金相变引起的体积变化;经计算得知,较之于热膨胀实验结果,该比容差法的相对误差在25%以内,表明比容差法具有一定的可靠性,且有较高的准确性;XRD的实验结果表明,不同热处理后的试样,残余应力的数值有所不同,从110MPa到300MPa,且均为压应力,残余应力出现从110MPa到300MPa的不同测试结果,就2024铝合金而言,时效温度为200℃时残余应力最大,之后随着时效温度的增高残余应力减小。结合比容差法的测量结果,得知时效后,铝合金的体积增大,由此引起其内部产生一定的残余压应力,且时效效果越明显,其残余压应力的数值也相应增大。47042
毕业论文关键词: 铝合金;热处理;比容差法;残余应力
Measurement of volume change and study of Residual stress of aluminum alloy under different heat treatment processes
Abstract:In this article,the specific volume difference method was used to study aluminum alloy’s volume change under different heat treatment process,then Thermal expansion test was conducted to verify this method.After that,XRD was applied to test the residual stress of aluminum alloy under heat treatment from the perspective of what aluminum alloy volume changes,in order to analysis the rules of the residual stress .The results show that aluminum alloy’s volume change could be weighed out with accuracy,and the relative error of Specific volume difference method less than 25% comparing the results of thermal expansion test by calculating,which indicated the feasibility and high accuracy of specific volume difference method.The results of XRD test indicated that the residual stress was compressive stress,and different for different heat treatment process samples,ranging from 110MPa to 300MPa.Specificly,as far as 2024 aluminum,residual stress was the largest aging at the temperature of 200℃,then it decreasd with the increase of aging temperature.According to the results of the specific volume difference method,it was discovered that with the ingcrease of aluminum volume under aging treatment,the residual stress emerged.And the results increased along with the increase of aging effect.
Keywords:aluminum alloy; Heat Treatment;Specific volume difference method;Residual Stress
目 录
1 绪论 1
1.1 铝合金简介 1
1.2 铝合金的时效处理 1
1.2.1 铝合金时效处理的目的 1
1.2.2 铝合金时效处理特点 2
1.2.3 铝合金时效强化原理 2
1.2.4 影响时效的因素 2
1.3 相变过程体积变化及残余应力测量的方法 4
1.3.1 体积变化测量方法 4
1.3.2 残余应力测试方法 4
1.4 研究目的与意义 5
1.5 研究内容与目标 6
2 实验内容 7
2.1 实验原料和设备 7
2.1.1 实验原料 7
2.1.2 实验设备 7
2.2 热处理实验