導(dǎo)致無縫方管點腐蝕的材料因素分析

今天小編為各位講解一下影響無縫方管點腐蝕的材料因素都有哪些。合金成分對無縫方管來說，0、10及F等元素是使合金具有良好抗點腐蝕性能的主要合金元素。其他一些元素也可能有一定的效果，K等元素則會降低無縫方管的抗點腐蝕能力。將合金元素對材料耐點腐蝕性的影響扼要地概括于有利影響是肯定的。13、0的影響是變化的。3在固溶體中是有益的，但當(dāng)作為中間金屬相析出時則有害，0在固溶體中是無害的，當(dāng)以碳化物析出時則有害，但稍有不利影響。
Today, Xiaobian will explain to you the material factors that affect the pitting corrosion of seamless square pipes. For seamless square tubes, elements 0, 10 and F are the main alloying elements which make the alloy have good resistance to pitting corrosion. Other elements may also have some effect, while K and other elements will reduce the pitting corrosion resistance of seamless square tubes. It is affirmative that the effect of alloying elements on the pit corrosion resistance of materials can be summarized briefly in terms of beneficial effects. The effects of 13 and 0 are variable. 3 is beneficial in solid solution, but harmful when precipitated as intermediate metal phase, 0 is harmless in solid solution and harmful when precipitated with carbide, but slightly harmful. (2)對奧氏體無縫方管進(jìn)行冷加工的研究表明，冷加工后試樣表面的蝕坑數(shù)目增多和蝕坑的尺寸變小。這是因為冷加工增加位錯密度，位錯在表面露頭處容易引起點腐蝕坑，冷加工有增加點腐蝕的趨勢。
(2) The research on cold-working of austenitic seamless square tubes shows that the number of pits on the surface of samples increases and the size of pits decreases after cold-working. This is due to the increase of dislocation density in cold processing, dislocation in the surface outcrop is prone to cause pitting corrosion, cold processing has the trend of increasing pitting corrosion.

(3)表面狀態(tài)對一個給定的合金環(huán)境體系，決定合金點腐蝕電位的因素乃是材料表面的光潔度。事實上，對具有不同表面光潔度的合金進(jìn)行點腐蝕傾向的比較是毫無意義的。關(guān)于表面光潔度對無縫方管點腐蝕性能影響情況如圖所示。它表明，在同樣的材料環(huán)境體系中，若表面光潔度不同，其點腐蝕電位的差別可在14以上。
(3) For a given alloy environment system, the factor that determines the pitting corrosion potential of the alloy is the smoothness of the material surface. In fact, it is meaningless to compare the pitting corrosion tendency of alloys with different surface finish. The effect of surface finish on the corrosion resistance of seamless square pipes is shown in the figure. It shows that in the same material environment system, if the surface finish is different, the difference of pitting corrosion potential can be more than 14.

(4)無縫方管在空氣中，由于加熱而形成的氧化物可能對抗點腐蝕性能有重大影響。由
(4) The oxide formed by heating in seamless square tubes in air may have a significant impact on the pitting corrosion resistance. from

顯微組織熱鍍鋅方管對合金抗點腐蝕性能起著重要作用。各種相，如硫化物夾雜、3鐵素體。相、敏化的晶界以及焊縫等都可能對鋼的抗點腐蝕性能具有決定性的影響，它們都是發(fā)生點腐蝕最敏感的部位。這對顯微組織較為復(fù)雜的鑄造無縫方管以及顯微組織對熱處理工藝十分敏感的馬氏體型無縫方管來說，點腐蝕與組成相的關(guān)系就更為密切。需要指出的是，含的復(fù)合硫化錳夾雜是點腐蝕更敏感的部位。因此，在冶煉無縫方管時，應(yīng)避免采用鋁脫氧劑。
Microstructure galvanized square tubes play an important role in the pitting corrosion resistance of the alloy. Various phases, such as sulphide inclusions and 3 ferrite. Phases, sensitized grain boundaries and welds may have a decisive impact on the pit corrosion resistance of steel. They are the most sensitive sites for pit corrosion. For the cast seamless square tubes with complex microstructures and martensitic seamless square tubes with sensitive microstructures to heat treatment process, the relationship between pitting corrosion and constituent phases is more close. It should be pointed out that the complex manganese sulfide inclusions are more sensitive to pitting corrosion. Therefore, aluminium deoxidizer should be avoided in the smelting of seamless square tubes.

(5)焊接所產(chǎn)生的氧化膜對合金在烈性氯化物溶液中的抗點腐蝕性能可能是不利的。
(5) The oxide film produced by welding may be detrimental to the pitting corrosion resistance of the alloy in the strong chloride solution.

(6)鈍化處理的主要作用是溶解無縫方管表面的夾雜物和沾染物，使之潔凈，它還可去掉表面的硫化錳夾雜，這種夾雜可能成為點腐蝕的萌生源、從而改善無縫方管的抗點腐蝕性能。需要注意的是，無縫方管在鈍化處理后應(yīng)用氫氧化鈉溶液清洗
(6) The main function of passivation treatment is to dissolve the inclusions and contaminants on the surface of seamless square tubes and make them clean. It can also remove the manganese sulfide inclusions on the surface. Such inclusions may become the origin of pitting corrosion and thus improve the pitting corrosion resistance of seamless square tubes. It should be noted that seamless square tubes are cleaned with sodium hydroxide solution after passivation treatment.

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