工業冷拔無縫鋼管腐蝕表現在哪些地方
工業冷拔鋼管的腐蝕主要表現在:冷拔鋼管的一種嚴重的腐蝕形式是局部腐蝕(亦即應力腐蝕開裂、點腐蝕、晶間腐蝕、腐蝕疲勞以及縫隙腐蝕)。接下來冷拔無縫鋼管廠傢來重點的介紹下。冷拔無縫鋼管是用來描述在整個合金表面上以比較均勺的方式所發生的腐蝕現象的術語。當發生全面腐蝕時,村料由於腐蝕而逐漸變薄,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.
應力腐蝕開裂(SCC):是指承受應力的合金在腐蝕性环境中由於烈紋的擴展而互生失效的一種通用術語。應力腐蝕開裂具有脆性斷口形貌,但它也可能發生於韌性高的材料中。發生應力腐蝕開裂的必要條件是要有拉應力(不論是殘餘應力還是外加應力,或者兩者兼而有之)和特定的腐蝕介質存在。型紋的形成和擴展大致與拉應力方向垂直。這個導致應力腐蝕開裂的應力值,不銹鋼工業冷拔鋼管要比沒有腐蝕介質存在時材料斷裂所需要的應力值小得多。在微觀上,穿過晶粒的裂紋稱為穿晶裂紋,而沿晶界擴圖的裂紋稱為沿晶裂紋,當應力腐蝕開裂擴展至其一深度時(此處,承受載荷的材料斷面上的應力達到它在空氣中的斷裂應力),則材料彩色沥清地坪就按正常的裂紋(在韌性材料中,通常是通過顯微缺陷的聚合)而斷開。因此,由於應力腐蝕開裂而失效的零件的斷面,將包含有應力腐蝕開裂的特征區域以及與已微缺陷的聚合相聯系的“韌窩”區域。
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 it环氧地坪s 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.
點腐蝕:是一種導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:晶粒間界是結晶學取向不同的晶粒間紊亂錯合的界城,因而,它們是鋼中各種溶質元素偏析或金屬化合物(如碳化物和δ相)沉淀析出的有利區城。因此,在某些腐蝕介質中,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,大多數的金屬和合金在特定的腐蝕介質中都可能呈現晶間腐蝕。
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,它可能發全於溶液停滯的縫隙之中或屏蔽的表面內。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.