外文翻譯--半連不銹鋼aisi 304的等離子膏劑滲硼處理

1、<p>　　Plasma paste boroniding treatment of the stainless steel AISI 304</p><p>　　1.Introduction</p><p>　　AA3003 alloys in recent years, the development of surface treatment process has been

2、 extensive research to improve the application of stainless steel under high temperature and pressure wear and oxidation resistance. Stainless steel surface treatment methods available, including nitrogen [2], carburizin

3、g, plasma coating, boron penetration In particular, the boride is boron penetration and diffusion into the surface of the boride layer (hardness (HV) between in 1300-2100) of the surface treatment</p><p>　　R

4、ecently, however, improved technology such as plasma Boronizing infiltration process has been extensively studied, because the traditional boronizing process, such as the official salt-bath and gas nitriding boron-boron

5、will appear, such as environmental pollution, toxic, explosive nature of the problem.</p><p>　　Plasma boronizing has many advantages over traditional boronizing process. For example, expect a high energy eff

6、iciency as a source of high-energy plasma to be used in plasma boronizing process, and distortion can be minimized, because the processing temperature is relatively lower than the traditional process. However, plasma bor

7、onizing process also has its own limitations. BZH6 and BC13 gas was used as a boron source gas, but gas is relatively expensive and toxic, explosive. In a vacuum chambe</p><p>　　In this study, as the develop

8、ment of a solution to the problem mentioned above and more in the process of boron penetration in one attempt, involving the use of amorphous boron and borax (Na2B4O7) cream is a simple process of plasma Pasty boronizing

9、 methods have been designed, the best plasma boronizing paste has conducted a survey of process conditions, thus the formation of boride layer method has certain characteristics</p><p>　　2.Experimental</p

10、><p>　　The real AISI304 stainless steel specimens (diameter 15 mm, thickness 2.5 mm) was used for this test. Sandpaper (# 1200), after polishing the surface of the sample specimen, clean off the dirt after the

11、samples are brought into the laboratory, in the H2 atmosphere for sputter cleaning of the specimen is the first to be carried out. In Ar: H2 (2:1) gas environment, with different proportions of boron and borax mixture of

12、 boron penetration agents do boronizing plasma treatment began, in 1023,1073,</p><p>　　3.Results and discussion</p><p>　　3.1 Cream mixture ratio of boride layer formation</p><p>　　F

13、ig1 The effect of various ratios of amorphous boron and borax mixture</p><p>　　thickness of the boride layer.</p><p>　　Fig.1 shows the proportion of paste with different boride in the 1123 K tem

14、perature insulation 1.5 hours after the boride layer thickness. Observed with the mass fraction of 20% and 70% of borax to form a thick boride layer. And with the mass fraction of 100% of amorphous boron to form any meas

15、urable thickness of boride layer is not observed, which may be attributed to the penetration of boron in plasma during the amorphous boron as the melting point due to surface diffusion of the lack of activ</p><

16、;p>　　When the mass fraction of borax to 20%, the active form of the boride layer was observed. During the infiltration of boron, boron atoms, B0, is cream of the boron hydride (BnHm) of decomposition, and the boron at

17、oms into the molten borax or B0 glow discharge in the active boron atoms B +1. Finally, the boron atoms, B +1, proliferation, and iron reaction, and then the formation of boride layer. With the mass fraction of 30% and 7

18、0% of the boron paste of borax boride layer formation was also obser</p><p>　　Moreover, the mass fraction of 40 and 55% of the paste, when the slow rate of boride was observed, as shown in Figure 1. Presumab

19、ly, for including gas, electrolysis, electrolysis, etc., a variety of non-liquid boronizing mechanism, the active ingredient in this range will be difficult for some reason, the need for further investigation.</p>

20、<p>　　Figure 1 stainless steel boride layer thickness less than mild carbon steel, which confirms previously reported results [7,8]. Not only because of the stainless steel surface has a protective layer, but also

21、in chrome, nickel boride on the surface but also the protective layer, they form with the grain boundary, thereby preventing the diffusion of boron [7,8]. It was also pointed out that, due to the increase in the number o

22、f boron, paste becomes excessive, adhesive on the surface when the plasm</p><p>　　3.2Effect of temperature and time on the rate of formation of the boride layer</p><p>　　Fig. 2. Relation between

23、 the boroniding temperature and times on the</p><p>　　Figure 2 shows the temperature and time on the boride boride layer depth. According to the parabolic theory, with the infiltration time and temperature i

24、ncreased boron, boride layer depth will also increase. This shows that the boride layer formation rate becomes slow as time increases boron penetration. This can be explained by the fact that: the formation of boride lay

25、er on the surface of the Ni-rich layer below and chromium-rich layer plays the role of diffusion barrier, inhibit the activity </p><p>　　3.3 Changes in cross-section hardness distribution</p><p>

26、;　　Fig. 3. Hardness curves of AISI 304 boronized for various times at 1173 K.</p><p>　　Plasma boride specimens in 1023,1073,1123 K, holding seven hours to get the boride layer thickness can not be measured,

27、and their hardness measurement is impossible. In 1173 and 1223K temperature plasma boronizing, in any case, the formation of 30 to 40 microns thick boride layer; boride samples of plasma for 7 hours at 1223K cross-sectio

28、n hardness measurement results are summarized in Figure 3 on. Boride in plasma 7 hours after the specimens found on the maximum depth of the nitrided layer of 4</p><p>　　3.4 Boride layer cross-section micros

29、tructure and composition analysis of</p><p>　　Fig. 4. Microstructure of the boride layer.</p><p>　　For AISI304 stainless steel processing in 1023 ~ 1223K 3,5,7 hours of boride layer cross-sectio

30、nal study of micro-structural inspection found that with the infiltration of growth temperature and time of boron, followed by growth of boride layer thickness. Boronizing carbon steel in the normal tooth structure obser

31、ved in the stainless steel observed in the boride not. On the contrary, as shown in Figure 4, in 1173K after 3 hours of boride boride layer of stainless steel flat structure emerged.</p><p>　　Plasma cross-se

32、ction of boride specimens show a layer of micro-structure of boride layer, Ni-rich layer, chromium-rich layer, as well as the matrix, and other researchers observed results. Figure 4 electron probe composition analysis o

33、f each region. The results showed that boride layer containing about 4 wt nickel, base and about 7.5 Ni. This explains the boride layer under the Ni-rich layer formation. During the plasma boronizing, when excess nickel

34、boride layer needs to spread to the substrate</p><p>　　In addition, Katagiri observed in the boride layer with small pores and boron trichloride, hydrogen for the formation of iron boride boride layer simila

35、r to the pores. Because these pores on the mechanical properties of diffusion layer is detrimental, so a lot of holes to determine the formation mechanism of these studies have been carried out. To date, the boron in the

36、 boride layer in the heterogeneous distribution of boride layer is generally considered the main reason for the formation of the</p><p>　　4.Conclusions</p><p>　　(1) Of AISI304 stainless steel pl

37、asma boronizing paste, the formation of boride layer of the most effective and most economical cream ratio is 30% mass fraction of amorphous boron and 70% of borax.</p><p>　　(2) Plasma Pasty boronizing metho

38、d than the traditional method of thermal diffusion boride in a shorter time and lower temperatures, has been flattened thick boride layer.</p><p>　　(3) Plasma Pasty boride of AISI304 stainless steel micro-st

39、ructure from far and near are the boride layer, the Ni-rich layer, the chromium-rich layer, matrix, etc. Boron in the process of infiltration, with low solubility of nickel boride layer formed on the surface, excessive n

40、ickel boride layer by diffusion in the formation of Ni-rich layer below. Some elements into the Cr boride layer, and some spread to the substrate, resulting in Ni-rich layer between the substrate and the formation of chr

41、o</p><p>　　(4) AISI304 stainless steel form a boride layer of the activation energy is 123 kJ per mole, which is significantly lower than the traditional method to measure the thermal diffusion of boron pene

42、tration into the data.</p><p>　　半連不銹鋼AISI 304的等離子膏劑滲硼處理</p><p><b>　　1、概述</b></p><p>　　AA3003合金近年來， 對表面處理工藝的發(fā)展已在廣泛的研究，以改善不銹鋼在高溫高壓應(yīng)用下的磨損和抗氧化性能。不銹鋼可用的表面處理方法包括氮化，滲碳，等離子涂層，滲硼

43、。特別是，滲硼是通過滲透和擴散硼到表面形成硼化物層（硬度（HV）在1300至2100之間）的表面處理方法。硼化物層也有出色的耐熱性和抗腐蝕性，并且滲硼已應(yīng)用于改善閥門，燃燒器，噴嘴等的表面性能，當它們在高溫高壓下暴露在水和油中時。</p><p>　　然而，最近經(jīng)過改良的滲硼工藝如等離子滲過程已經(jīng)廣泛的研究，因為傳統(tǒng)的滲硼工藝，如正式鹽浴滲硼和氣體滲硼會出現(xiàn)如環(huán)境污染，毒性，爆炸性性質(zhì)等問題。</p>

44、<p>　　等離子滲硼擁有許多優(yōu)勢比傳統(tǒng)的滲硼工藝。例如，一個高能源效率期望作為一種等離子高能量的來源被利用在等離子滲硼過程中，而且變形可以被盡量減少，因為加工溫度相對低于傳統(tǒng)工藝。然而，等離子滲硼進程也有其自身的局限。 BZH6和BC13氣體被用來作為硼源氣體，但這些氣體相對昂貴，而且有毒，有爆炸性。在真空室中通過硼氯腐蝕是另一個嚴重的問題對等離子滲硼來說。</p><p>　　在這項研究中，作為

45、發(fā)展一種解決上述提到問題的滲硼工藝的多中嘗試中的一種，涉及到用無定形硼和硼砂（Na2B4O7）膏劑的一種簡單處理的等離子膏劑滲硼法已經(jīng)被設(shè)計，最佳的等離子膏劑滲硼工藝條件已經(jīng)進行了調(diào)查，由此法形成的硼化物層已有一定特點。</p><p><b>　　2、實驗方法</b></p><p>　　本實AISI304不銹鋼標本（直徑15毫米，厚度，2.5毫米）被用于此次試驗。

46、砂紙（＃1200級）拋光標本試樣表面后，干凈脫污后的標本被帶入實驗室，在H2氛圍中對標本進行濺射清洗是首先要進行的。在Ar：H2（2：1）的氣體環(huán)境中，用不同配比的硼和硼砂的混合物做滲硼劑的等離子滲硼處理開始了，要在1023，1073，1123，1173和1223 K幾個不同溫度下加熱長達7個小時。用顯微掃描電鏡（日立5-2400）研究它的微觀結(jié)構(gòu)，在20千伏加速電壓下做了電子探針分析。維氏硬度測定使用了0.1公斤力負荷，采用7個讀數(shù)的

47、平均值。CuK射線衍射儀被用于X射線衍射分析。等離子膏劑滲硼用的器具和其他試驗的細節(jié)在參考文獻中用描述。</p><p><b>　　3、實驗結(jié)果及討論</b></p><p>　　3.1膏劑混合物的比例對硼化物層形成的影響</p><p>　　Fig1 The effect of various ratios of amorphous bor

48、on and borax mixture</p><p>　　thickness of the boride layer.</p><p>　　圖1. 不同配比的無定形硼和硼砂的混合物對硼化物層厚度的影響</p><p>　　圖.1顯示了用不同比例的膏劑滲硼在1123 K溫度下保溫1.5小時后硼化物層的厚度。觀察了用質(zhì)量分數(shù)為20%和70%的硼砂形成的厚硼化物層。而

49、用質(zhì)量分數(shù)為100%的無定形硼形成的任何可測量厚度的硼化物層沒有被觀察到，這可能歸因于在等離子滲硼期間由于無定形硼的高熔點造成的用于表面擴散的活性硼的缺少。</p><p>　　當硼砂的質(zhì)量分數(shù)增加到20%時，活躍形成的滲硼層被觀察。在滲硼期間，硼原子，B0，是通過膏劑中的硼的氫化物（BnHm）的分解產(chǎn)生的，而且這個硼原子B0變成熔融的硼砂或輝光放電里活躍的硼原子B+1。最后，這個硼原子，B+1，擴散，和鐵反應(yīng)，

50、然后形成硼化物層。用質(zhì)量分數(shù)為30%的硼和70%的硼砂的膏劑形成的硼化物層也被觀察，這可能歸因于有效的液態(tài)電解機制，當隨著膏劑中硼砂數(shù)量的增加，熔融硼砂的流動性增加的時候。</p><p>　　此外，用質(zhì)量分數(shù)40和55%的膏劑，滲硼時比較慢速率被觀察，正如圖1所示。據(jù)推測，對包括氣體，電解，液體非電解等在內(nèi)各種滲硼機制來說，活躍在這個成分范圍內(nèi)將是困難的，由于一些原因，因此需要進一步調(diào)查研究。</p>

51、;<p>　　圖1中不銹鋼硼化物層的厚度低于溫和的碳素鋼，這證實了以前報告過的結(jié)果[7,8]。這不僅是因為在不銹鋼的表面有一個防護層，而且在鉻，鎳等硼化物的表面也有防護層，它們形成與晶界，從而阻止了硼的擴散[7,8]。也有人指出，由于硼的數(shù)量的增加，膏劑變得過量，粘著在標本的表面當?shù)入x子膏劑滲硼開始后，導致這膏劑的回收率非常低?？紤]到硼元素的高成本，因此推斷出等離子膏劑滲硼用的最佳膏劑成分是質(zhì)量分數(shù)30%的無定形硼和70%

52、的硼砂。</p><p>　　3.2溫度和時間對滲硼層形成率的影響</p><p>　　Fig. 2. Relation between the boroniding temperature and times on the</p><p>　　thickness of the boride layer.</p><p>　　圖2 滲硼溫度

53、和時間之間的關(guān)系對硼化物層深度的影響</p><p>　　圖2顯示了滲硼溫度和時間對硼化物層深度的影響。根據(jù)拋物線原理，隨著滲硼時間和溫度的增加，硼化物層的深度也跟著增加。這表明硼化物層的形成率變的緩慢了隨著滲硼時間的增加。這可以用這樣一個事實解釋：形成于表面的硼化物層的下面的富鎳層和富鉻層扮演了擴散屏障的角色，抑制活性硼擴散。進一步的解釋將在文章后面給出。</p><p>　　3.3截面

54、硬度分布的變化</p><p>　　Fig. 3. Hardness curves of AISI 304 boronized for various times at 1173 K.</p><p>　　圖3. AISI304不銹鋼在1173K下硼化時，不同時間的硬度曲線</p><p>　　等離子滲硼標本在1023，1073，1123K，保溫7個小時得到的硼化

55、物層厚度不能被測量，它們的硬度測量也是不可能的。在1173和1223K溫度下等離子滲硼，無論如何，形成了30～40微米厚的硼化物層；對等離子滲硼標本在1223K保持7小時后的截面硬度測量結(jié)果總結(jié)在圖3上。在等離子滲硼7小時后的標本上發(fā)現(xiàn)了最大深度為45微米的滲層，和最高硬度為1800～2000的滲層。</p><p>　　3.4截面硼化物層的微觀結(jié)構(gòu)和成分分析</p><p>　　Fig.

56、 4. Microstructure of the boride layer.</p><p>　　圖4.硼化物層的微觀結(jié)構(gòu)</p><p>　　對AISI304不銹鋼在1023～1223K處理3，5，7個小時的滲硼層的截面微觀結(jié)構(gòu)檢查研究后，發(fā)現(xiàn)隨著滲硼溫度和時間的增長，硼化物層厚度也跟著增長。在滲硼碳鋼中能正常觀察到的齒狀結(jié)構(gòu)在滲硼不銹鋼中觀察不到。相反，如圖4所示，在1173K滲硼3

57、小時后的不銹鋼硼化物層中出現(xiàn)了扁平結(jié)構(gòu)。</p><p>　　等離子滲硼標本的截面微結(jié)構(gòu)顯示了一層硼化物層，富鎳層，富鉻層，還有基體，和其他研究者觀察的結(jié)果一致。用電子探針對圖4的每個區(qū)域進行成分分析。結(jié)果顯示硼化物層含大約質(zhì)量分數(shù)為4的鎳，基體還有大約7.5的鎳。這解釋了在硼化物層下的富鎳層的形成。在等離子滲硼期間，當硼化物層中過量的鎳需要擴散到基體時，富鎳層在硼化物層和基體之間形成。另外，觀察圖4中在富鎳層下

58、的富鉻層（大約質(zhì)量分數(shù)為28%的鉻）。根據(jù)目前用電子探針對硼的線性分析，在等離子滲硼期間，觀察到硼化物層有高度的硼集中現(xiàn)象，富鉻區(qū)硼的高度集中也被探測到，這表明在這個區(qū)域有大量的鉻硼化物形成。</p><p>　　此外，Katagiri觀察了硼化物層中的小氣孔和用氯化硼，氫氣對純鐵滲硼形成的硼化物層中相似的氣孔。由于這些氣孔對滲層的機械性能是不利的，所以大量的判斷這些氣孔形成機制的研究已經(jīng)進行。迄今為止，硼在硼化

59、物層中的異構(gòu)分布被普遍認為是硼化物層中氣孔形成的主要原因。據(jù)報道，擴散退火處理時有效去除滲層氣孔的方法。</p><p><b>　　.</b></p><p><b>　　4、結(jié)論</b></p><p>　　（1）對AISI304不銹鋼的等離子膏劑滲硼來說，形成硼化物層的最有效、最經(jīng)濟的膏劑配比是質(zhì)量分數(shù)30%的無定形

60、硼和70%的硼砂。</p><p>　?。?）用等離子膏劑滲硼法，可以比傳統(tǒng)的熱擴散滲硼法在一個較短時間和較低溫度下，得到扁平結(jié)構(gòu)的厚硼化物層。</p><p>　　（3）用等離子膏劑滲硼的AISI304不銹鋼的微觀結(jié)構(gòu)由遠及近分別是硼化物層，富鎳層，富鉻層，基體等。在滲硼過程中，含低溶解度鎳的硼化物層形成在表面，過量的鎳通過擴散在硼化物層下面形成富鎳層。Cr元素中的一些進入硼化物層，另一