摘要
采用单辊甩带法制备(Fe_(0.52)Co_(0.18)Ni_(0.30))_(73)Cr_(17)Zr_(10)全金属铁基非晶合金,对其进行不同的结构弛豫处理,即在低于玻璃转化温度(T_(g)=825 K)下725 K进行0 h、0.5 h、2 h、4 h、10 h真空退火热处理,获得不同结构状态的非晶合金,并在玻璃转化温度以上925 K进行真空晶化处理,保温10 min得到晶态(Fe_(0.52)Co_(0.18)Ni_(0.30))_(73)Cr_(17)Zr_(10)。用XRD测试试样物相组成,并用DSC分析热力学参数,得出结构弛豫焓(ΔH_(fv)),然后计算相应的自由体积含量(V_(0));用电化学工作站测试试样在3.5%(质量分数,下同)NaCl溶液中的电化学腐蚀性能;用SEM观察试样腐蚀形貌,并用EDS测试元素种类和含量。结果表明,一定程度的结构弛豫能降低非晶合金中的自由体积量,使原子堆积更加紧密、结构更加稳定,从而提高非晶合金的抗均匀腐蚀性能和抗点蚀性能,其中0.5 h和2 h时结构弛豫的效果最佳;而结晶态和长时间结构弛豫则会提高非晶合金的点蚀敏感性,降低钝化膜致密度,从而加剧腐蚀。
(Fe_(0.52)Co_(0.18)Ni_(0.30))_(73)Cr_(17)Zr_(10)all-metal Fe-based amorphous alloy was fabricated by means of melt spinning and subjected to different structural relaxation treatments.Vacuum annealing heat treatment for 0 h,0.5 h,2 h,4 h and 10 h at 725 K below the glass transition temperature(T_(g)=825 K)was carried out so as to obtain amorphous alloys with different structural states.Vacuum crystallization was carried out at 925 K above the glass transition temperature and then holding for 10 min so as to obtain the crystalline(Fe_(0.52)Co_(0.18)Ni_(0.30))_(73)Cr_(17)Zr_(10).The phase composition of the samples was tested by XRD,the thermodynamic parameters were analyzed by DSC to obtain the structural relaxation enthalpy(ΔH_(fv)),and then the content of corresponding free volume(V_(0))was calculated.The electrochemical corrosion resistance in 3.5 wt%NaCl solution was tested by electrochemical workstation.The corrosion morphology was observed by SEM and the type and content of elements were tested by EDS.The results show that a certain structural relaxation can reduce the free volume in the amorphous alloy,which makes the atomic stacking closer and the structure more stable so as to improve the uniform corrosion resistance and pitting corrosion resistance,among which structural relaxation for 0.5 h and 2 h has the best effect.The crystalline and long-time structural relaxation will improve the pitting corrosion sensitivity of amorphous alloys,reduce the density of passive film,and aggravate the corrosion.
作者
胡家富
谢春晓
陶平均
HU Jiafu;XIE Chunxiao;TAO Pingjun(School of Materials and Energy,Guangdong University of Technology,Guangzhou 510006,China;College of Mechanical Engineering,Dongguan University of Technology,Dongguan 523808,Guangdong,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2022年第S01期360-364,共5页
Materials Reports
基金
国家自然科学基金(5217010020)
关键词
结构状态
全金属铁基非晶合金
结构弛豫
晶化处理
腐蚀性能
structural state
all-metal Fe-based amorphous alloy
structural relaxation
crystallization treatment
corrosion property
