نوع مقاله : مقاله کامل پژوهشی

نویسندگان

1 پژوهشکده مواد پیشرفته و انرژیهای نو، سازمان پژوهشهای علمی و صنعتی ایران

2 پژوهشکده مواد پیشرفته و انرژیهای نو، سازمان پژوهش های علمی و صنعتی ایران،

چکیده

در این پژوهش جاذب[mk1] ی با ترکیب 75 درصد وزنی زیرکونیم، 22 درصد وزنی کبالت، 1.5 درصد وزنی پرزدمیم و 1.5 درصد وزنی نئودمیم سنتز شده است تا تاثیر این عناصر بر شرایط فعال­سازی و خواص جذبی آن [mk2] بررسی و با تاثیر ایتریم مقایسه شود. با توجه به اکتیویته بالای جاذب­های تبخیر نشونده، برای از بین بردن لایه اکسیدی، نمونه­ها ابتدا به مدت 20 دقیقه در دمای  100 قرار داده شده و سپس به مدت 80 دقیقه در دماهای  360 فعال شدند. نتایج تست جذب بر حسب تغییرات فشار و دما زمان مشخص که شروع دمای فعال­سازی برای نمونه حاوی ایتریم تقریبا 60 درجه کاهش داشته و از  260 به  200 رسیده است. فشار شروع تست جذب در محفظه جاذب برای همه نمونه ها 1.5×10-5 mmHg بوده که فشار نهایی سیستم با جاذب حاوی ایتریم کمترین میزان را داشته و برابر باmmHg 1.3×10-6است. همچنین بعد از پایان فعال­سازی و ثبت فشار نهایی ارتباط بین راکتور و پمپ­های خلاء قطع شده تا زمان لازم برای شکستن خلاء از mmHg001/0 تا mmHg 2/0 مشخص شود. حداکثر زمان شکستن خلاء برای نمونه حاوی ایتریم بوده که برابر با 4955 ثانیه می­باشد. با توجه به نتایج به دست آمده، عملکرد پرزدمیم، نئودمیم و ایتریم نزدیک به یکدیگر بوده و هر 3 عنصر نزدیک به ده برابر فشار سیستم را کاهش داده و زمان شکستن خلاء را به بالاتر از 4000 ثانیه افزایش داده اند.



 

کلیدواژه‌ها

عنوان مقاله [English]

Study of the effect of praseodymium and neodymium on adsorption properties for active gases in non-evaporable Zr-Co base chemical getter and comparing them with yttrium

نویسندگان [English]

  • Mehrdad Fattahzade 1
  • Ali Kaflou 2
  • Valiollah Dashtizad 1

1 Institute for Advanced Materials and New Energy, Iranian Scientific and Industrial Research Organization

2 Institute for Advanced Materials and New Energy, Iranian Scientific and Industrial Research Organization

چکیده [English]

In this research, a chemical getter with 75%wt zirconium, 22% cobalt, 1.5%wt of praseodymium and 1.5%wt neodymium was synthesized by ball milling. The effect of these elements on the adsorption/desorption properties of the getter was compared with the effect of yttrium. Due to the high activity of non-evaporable getters, oxide layers are formed on the surface. So, for activating a getter these layers must be removed. For this purpose, the samples were first placed at 100 °C for 30 minutes and then were activated at 360 °C for 80 minutes. The results of the adsorption tests in terms of pressure and temperature variations versus time indicated that the activation temperature for the yttrium sample was reduced by about 60 degrees and reached from 260 to 200 °C. The start pressure of the adsorption test in the getter chamber for all samples is 1.5 × 10-5 mmHg. While in the case of Y the final pressure of the reactor was reached to 1.3 × 10-6 mmHg. After completion of the activation process, the connection between the reactor and the vacuum pumps was disconnected to determine the time of vacuum preserving from 0.001 to 0.2 mmHg. The required time to break the vacuum for yttrium containing sample was 4955 seconds, which has the highest value. According to the results, the performance of the Pr, Nd and Y is close to each other, and all of the  these elements reduced the pressure of the system by about ten times and increased the vacuum breaking time to more than 4000 seconds.

کلیدواژه‌ها [English]

  • Chemical getter
  • zirconium- cobalt
  • praseodymium
  • neodymium
  • yttrium
  • vacuum
  • activation
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