LC4鋁合金服役環(huán)境下點(diǎn)蝕形貌特征及其演變規(guī)律

LC4鋁合金服役環(huán)境下點(diǎn)蝕形貌特征及其演變規(guī)律Pitting Corrosion Topography Characteristics and Evolution Laws of LC4 Aluminum Alloy in Service Environment

為獲取飛機(jī)LC4鋁合金在服役環(huán)境下典型點(diǎn)蝕形貌特征，采用模擬服役環(huán)境的加速腐蝕實(shí)驗(yàn)環(huán)境譜對(duì)材料試件進(jìn)行加速腐蝕實(shí)驗(yàn)，定義3個(gè)參數(shù)蝕坑深度H、蝕坑表面長(zhǎng)度L、蝕坑表面寬度W為表征蝕坑形貌特征參量，跟蹤測(cè)量典型蝕坑不同腐蝕年限下此3個(gè)特征參量數(shù)值，獲取典型蝕坑形貌特征參量數(shù)據(jù)檢測(cè)結(jié)果。在此基礎(chǔ)上，對(duì)檢測(cè)結(jié)果分別采用統(tǒng)計(jì)分析和分形理論方法進(jìn)行數(shù)據(jù)分析，獲取LC4鋁合金同一腐蝕年限下和不同腐蝕年限下典型點(diǎn)蝕蝕坑的形貌特征及其演變規(guī)律。結(jié)果表明：同一腐蝕年限下，點(diǎn)蝕蝕坑形貌特征參量符合對(duì)數(shù)正態(tài)分布；隨著腐蝕年限的增加，點(diǎn)蝕蝕坑形貌特征參量逐漸體現(xiàn)出明顯的分形特征，蝕坑形貌逐漸趨向坑深度較淺、坑表面長(zhǎng)度較長(zhǎng)、坑表面寬適中的特征。

Aircraft aluminum alloy is easy to initiate pitting corrosion in the service environment, the pitting corrosion topography characteristics could directly affect the fatigue mechanical property of structure material. In order to obtain the pitting corrosion topography characteristics of LC4 aluminum alloy in the service environment, the accelerated corrosion test was carried out along the accelerated corrosion test environment spectrum which imitated the service environment spectrum, and the corrosion topography characteristic parameters of corrosion pit depth H,corrosion pit surface length L and corrosion pit surface width W were defined respectively. During the corrosion test process,the three parameters of typical corrosion pit were successively measured in different equivalent corrosion years for obtaining the corrosion pit damage size data, then the data were analysed through the statistics method and fractal theory. Further more in order to gain the pit topography characteristics in the same equivalent corrosion year and the topography evolution laws during different equivalent corrosion years were gained. The analysis results indicate that LC4 aluminum alloy corrosion pit topography characteristics in the service environment include the following:firstly, the pit topography characteristic parameters conform to the lognormal distributions in the same equivalent corrosion years; secondly,the pit topography characteristic parameters gradually reflect the fractal feature in accordance with the equivalent corrosion year increment, and the pits tend to be shallow, long and moderate wide topography character.

全文下載：http://pan.baidu.com/s/1jIOgGQi