钢的出气率的测量
Summary
A protocol for the measurement of outgassing rates of hydrogen from ordinary steel vacuum chambers using the rate-of-pressure rise method is presented.
Abstract
钢被常用材料在真空系统的制造，因为它们的良好的机械，腐蚀和真空特性。各种钢材满足低放气的高或超高真空应用所需的标准。然而，给定的材料可呈现取决于其制造过程中或在制造过程中涉及的各种前处理过程中不同出气率。因此，除气率的测量是对一个特定的真空应用高度期望的。出于这个原因，速率的压力上升（ROR）方法通常用于测量氢的烘烤后的释气。在这篇文章中，提供了设计和涉及回报率方法的实验方案的执行的详细描述。 RoR的方法使用纺纱转子计，以减少从脱气或真空计的泵送作用茎错误。两个普通钢的出气率（不锈钢和MILD钢）进行测定。该测量之前和钢的热预处理之后进行。进行钢的热预处理，以减少除气。除气极低的利率（10的顺序– 11帕米3秒– 1米 – 2）可以使用相对小样本进行常规检测。
Introduction
钢在建筑经常使用，因为其良好的机械性能。某些钢（亚铁钢，特别）是优选的材料包括真空应用。取决于类型和等级，这些钢具有足够低的出气率为高真空必不可少（HV，10 – 7 <P <10 – 5帕）或超高真空（UHV，10 -10 <P <10 – 7 Pa）的系统。此外，大量的研究已经朝着特殊的预处理程序，减少气体释放1-3的发展进行的。预处理措施旨在最小化泵送投资或改善真空从HV到UHV或从UHV极端高真空（P <10 – 10帕）。
虽然许多实际的方法已被提出，以减少除气鼠亚铁钢即，最近的方法主要集中在减少，以获得较低的放气速率所需要的时间和温度。在350°C-450°热治疗C，而不是在真空800℃，950℃烧制，是这种方法的一个很好的例子。 1,4,5此外，选择理想的材料为特定真空的应用是至关重要的;例如，选择的铁素体材料具有非常低的放气速率为在磁场屏蔽使用。 6,7
在这样的调查中，放气速率的精确测量对于候选材料的筛选或验证的各种预处理程序的有效性的一个先决条件。 8,9-用于脱气测量中的最常见的实验技术是可以通过和速率的压力上升的方法。 10日前，各种实验已经进行测量基础上，采用RoR的方法旋氢出气率宁转子计（SRG）。 1，11-13使用SRG的回报率的方法是非常适合测量非常低的氢出气率，往往限制了最低压力在由钢制成的真空系统可以实现的。这是因为，SRG具有可忽略泵送或除气动作。另外，SRG还具有在高真空和超高真空范围内具有优异的精度和良好的线性。 14
鉴于上RoR的实验已发表的文献中是有限的，这是值得来描述的实验细节，开发的方法的更深入的了解。在这个视频文章中，我们详细描述了建立实验的过程，并提供了详细的说明执行使用RoR的方法放气测量。为了证明该方法的功效，之前和预热处理后测定两种常用的钢（不锈钢304和软钢S20C）的出气率降低氢outgassin摹率。前和治疗后的值进行比较。使用相当简单的设置典型的实验结果呈现演示评价低氢脱气率优化的方法的功效。
Protocol
Representative Results
Discussion
为出气率的测量许多方法已在文献中报道。实验方法包括吞吐量，电导调制，双路径，回报率，和这些方法的变体。然而，没有一种方法适合获得必要的放气数据。 10使用SRG的回报率的方法，但是，成为首选低释气材料的测定方法。 11-13 SRG 17通常被用作在高真空系统，而不错误泵送或除气作用的二级标准。使用SRG RoR的方法特别适合于烘烤后测量氢气脱气室温。相比之下?…
Disclosures
The authors have nothing to disclose.
Acknowledgements
This work was supported jointly by the Converging Research Center Program through the Ministry of Science, ICT and Future Planning, Korea (NRF-2014M3C1A8048817) and R&D Convergence Program of NST (National Research Council of Science and Technology) of Republic of Korea (CAP-14-3-KRISS).
Materials
| Sample chamber | |||
| Stainless steel, 304 | POSCO (www.posco.co.kr) | ||
| Mild steel, D3752 | Xiangtan Iron&Steel co.,LTD (http://www.hnxg.com) | ||
| Mild steel, D3752 | SeAh Besteel (www.seahbesteel.co.kr) | ||
| Name | Company | Catalog Number | Comments |
| Cleaning | |||
| Cleaning bath | Samill IDS | Ultrasonic cleaning, heating, timer, concentration control | |
| Acetone | Samchun Chemical (www.samchun.com) | A1759 | HPLC GRADE (99.7%) |
| Tekusolv | NCH Co. (www.nch.com) | 0368-0058J | Solvents |
| BN cleaner | Henkel surface technologies (na.henkel-adhesives.com) | 6610263775 | Akkaline, pH 13 |
| Ethanol | Fisher Scientific (www.fishersci.com) | A995-4 | HPLC Reagent(99.9%) |
| Deionized water (Electro deionizer SYSTEM) | A.T.A (www.atagroup.co) | EDI SYSTEM | |
| Liquid N2 gas | Hanyoung (www.gasmaster.co.kr) | B/T 176 L | LN2 dewar, purity 99.999% |
| Name | Company | Catalog Number | Comments |
| Welding | |||
| Tungsten Inert Gas wedling machine | Thermal Arc (www.victortechnologies.com/thermalarc) | 400GTSW | Ar gas prefllow&postflow 8 liter/min, backflow 5 liter/min |
| turning jig | Vactron (www.vactron.co.kr) | Made to order | Made to order |
| Ar gas | Lindekorea (www.lindekorea.com) | Purity 99.999% | |
| Name | Company | Catalog Number | Comments |
| Leak test | |||
| Leak detector | Adixen (www.adixen.fr/en/) | ASM380 | Pumping Speed(air): 9.7 l/s |
| He gas | Lindekorea (www.lindekorea.com) | Purity 99.999% | |
| Name | Company | Catalog Number | Comments |
| Vacuum equipment | |||
| Spinning rotor gauge | MKS Instruments (www.mks.com) | SRG-3 | Controller, head, and thimble set |
| Industrial level meter | MKS Instruments (www.mks.com) | SRG-3 | For SRG assemble ± 1˚ |
| Oscilloscope | Tektronix (www.tek.com) | TDS2012B | |
| Residulal gas analyser | Balzers | QMA200 | m/e 0-100 |
| TMP(HiPace 80) | Pfeiffer Vacuum (www.pfeiffer-vacuum.com) | PMP03941 | Pumping Speed(N2): 67 l/s |
| Scroll pump | Anest Iwata (www.anest-iwata.co.jp) | ISP 90 | Pumping Speed(Air): 1.8 l/s |
| All-metall easy close angle valve(CF35) | VAT Inc. (www.vatvalve.com) | 54032-GE02-0002 | Rotatable flange |
| Angle valve(KF25) | MDC Vacuum Inc. (www.mdcvacuum.com) | KAV-100 | |
| Five-Way Crosses | MDC | Made to order | CF4-1/2 Spool-rotatable 1-way to CF2-3/4 Nipple 3ea, Vacuum degassed at 400℃ for 3 days |
| Reducing Tees | MDC | Made to order | CF4-1/2 Flange to CF2-3/4 Tees(Half flange), Vacuum degassed at 400℃ for 3 days |
| Name | Company | Catalog Number | Comments |
| Temperature control | |||
| Chiller | JEIO Tech (www.jeiotech.com) | RW-2025G | |
| Cooling line | LS Metal (www.lsmetal.biz) | C1100 | Level Wound Coil, Diameter 10mm |
| Heater controllers | HMT | Made to order | Bakeout program controller |
| Electrical heater tapes | Brisk heat (www.briskheat.com) | BIH101080L | |
| Thermocouple(K type) | miraesensor (www.miraesensor.com) | MR-2290 | |
| Handheld multimeter | Saehan (www.saehan.co.kr) | 3234 | |
| Data recorder(Temp.) | Yokogawa (www.yokogawa.com) | GP10-1E1F-UC10 | |
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