工業(yè)冷拔鋼管的腐蝕主要表現(xiàn)在:冷拔鋼管的一種嚴(yán)重的腐蝕形式是局部腐蝕(亦即應(yīng)力腐蝕開裂、點(diǎn)腐蝕、晶間腐蝕、腐蝕疲勞以及縫隙腐蝕)。接下來(lái)冷拔無(wú)縫鋼管廠家來(lái)重點(diǎn)的介紹下。冷拔無(wú)縫鋼管是用來(lái)描述在整個(gè)合金表面上以比較均勺的方式所發(fā)生的腐蝕現(xiàn)象的術(shù)語(yǔ)。當(dāng)發(fā)生全面腐蝕時(shí),村料由于腐蝕而逐漸變薄,甚至材料腐蝕失效。
Corrosion of industrial cold-drawn steel pipes is mainly manifested in: a serious form of corrosion of cold-drawn steel pipes is local corrosion (i.e. stress corrosion cracking, pitting corrosion, intergranular corrosion, corrosion fatigue and crevice corrosion). Next, cold-drawn seamless steel pipe manufacturers to focus on the introduction. Cold-drawn seamless steel pipe is a term used to describe the corrosion phenomena occurring on the whole alloy surface in a relatively uniform manner. When the overall corrosion occurs, the village materials gradually become thinner due to corrosion, and even the materials become corroded and invalid.
應(yīng)力腐蝕開裂(SCC):是指承受應(yīng)力的合金在腐蝕性環(huán)境中由于烈紋的擴(kuò)展而互生失效的一種通用術(shù)語(yǔ)。應(yīng)力腐蝕開裂具有脆性斷口形貌,但它也可能發(fā)生于韌性高的材料中。發(fā)生應(yīng)力腐蝕開裂的必要條件是要有拉應(yīng)力(不論是殘余應(yīng)力還是外加應(yīng)力,或者兩者兼而有之)和特定的腐蝕介質(zhì)存在。型紋的形成和擴(kuò)展大致與拉應(yīng)力方向垂直。這個(gè)導(dǎo)致應(yīng)力腐蝕開裂的應(yīng)力值,不銹鋼工業(yè)焊管要比沒(méi)有腐蝕介質(zhì)存在時(shí)材料斷裂所需要的應(yīng)力值小得多。在微觀上,穿過(guò)晶粒的裂紋稱為穿晶裂紋,而沿晶界擴(kuò)圖的裂紋稱為沿晶裂紋,當(dāng)應(yīng)力腐蝕開裂擴(kuò)展至其一深度時(shí)(此處,承受載荷的材料斷面上的應(yīng)力達(dá)到它在空氣中的斷裂應(yīng)力),則材料就按正常的裂紋(在韌性材料中,通常是通過(guò)顯微缺陷的聚合)而斷開。因此,由于應(yīng)力腐蝕開裂而失效的零件的斷面,將包含有應(yīng)力腐蝕開裂的特征區(qū)域以及與已微缺陷的聚合相聯(lián)系的“韌窩”區(qū)域。
Stress corrosion cracking (SCC) is a general term used to describe the alternating failure of stress-bearing alloys in corrosive environments due to the expansion of streaks. Stress corrosion cracking has brittle fracture morphology, but it may also occur in materials with high toughness. The necessary condition for stress corrosion cracking is the existence of tensile stress (whether residual stress or applied stress, or both) and specific corrosion medium. The formation and extension of the pattern are approximately perpendicular to the direction of tensile stress. This stress value, which leads to stress corrosion cracking, is much smaller than that required for material fracture without corrosive medium in stainless steel industrial welded pipe. Microscopically, cracks passing through grains are called transgranular cracks, while cracks extending along grain boundaries are called intergranular cracks. When stress corrosion cracks extend to a depth (where the stress on the load-bearing material section reaches its fracture stress in the air), the material breaks off according to normal cracks (in ductile materials, usually through the aggregation of micro-defects). Therefore, the section of the part which has failed due to stress corrosion cracking will contain the characteristic area of stress corrosion cracking and the "dimple" area associated with the aggregation of micro-defects.
點(diǎn)腐蝕:是一種導(dǎo)致腐蝕的局部腐蝕形式。
Point corrosion: A localized form of corrosion that results in corrosion.
晶間腐蝕:晶粒間界是結(jié)晶學(xué)取向不同的晶粒間紊亂錯(cuò)合的界城,因而,它們是鋼中各種溶質(zhì)元素偏析或金屬化合物(如碳化物和δ相)沉淀析出的有利區(qū)城。因此,在某些腐蝕介質(zhì)中,晶粒間界可能先行被腐蝕乃是不足為奇的。這種類型的腐蝕被稱為晶間腐蝕,大多數(shù)的金屬和合金在特定的腐蝕介質(zhì)中都可能呈現(xiàn)晶間腐蝕。
Intergranular corrosion: Intergranular boundaries are the boundaries of disordered and mismatched grains with different crystallographic orientations. Therefore, they are favorable areas for the segregation of various solute elements or precipitation of metal compounds (such as carbides and delta phases) in steel. Therefore, it is not surprising that grain boundaries may be corroded first in some corrosive media. This type of corrosion is called intergranular corrosion. Most metals and alloys may exhibit intergranular corrosion in a specific corrosion medium.
縫隙腐蝕:是局部腐蝕的一種形式,它可能發(fā)全于溶液停滯的縫隙之中或屏蔽的表面內(nèi)。這樣的縫隙可以在金屬與金屬或金屬與非金屬的接合處形成,例如,在與鉚釘、螺栓、墊片、閥座、松動(dòng)的表面沉積物以及海生物相接燭之處形成。
Crevice corrosion: A form of localized corrosion that may occur entirely in a solution-stagnated crevice or in a shielded surface. Such gaps can be formed at metal-to-metal or metal-to-metal joints, such as where rivets, bolts, gaskets, seats, loose surface sediments, and candles are joined to marine life. 無(wú)錫鑫盛源鋼管有限公司專業(yè)生產(chǎn):方管,矩形管,焊管等一系列高頻焊管產(chǎn)品,方管規(guī)格:40~200之間任意變形,矩形管規(guī)格:50~200之間任意變形,圓管規(guī)格:50~200之間任意變形.方管按生產(chǎn)標(biāo)準(zhǔn)分:國(guó)標(biāo)方管,日標(biāo)方管,英制方管,美標(biāo)方管,歐標(biāo)方管,非標(biāo)方管等.方管價(jià)格,矩形管價(jià)格,焊管價(jià)格.方管行情,矩形管行情,焊管行情.行業(yè)資訊
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