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The study of the duration of mechanical resistance to static tensile stress (withstand time) for an aluminum wire that being suffers from the corrosion effect stimulated by stray currents at different temperatures. Test device was designed and produced locally "in advance" in accordance with the specification (ASTM G103 - 97) to create static tensile stress of (1 N) on an aluminum wire of type ASTM (B231/B231M) with particular dimensions and utilized in the transmission of electrical energy, and when the wire is surrounded by a corrosive environment (NaCl solution) (3.5 % NaCl) at three different temperatures (25, 50, and 75 ° C) without any external electrical current causing corrosion; this symbolizes stray currents. Then compare the findings of that example to the results of the same wire's withstand time in the presence of an external electrical current generated by corrosion of type (D.C) by (5V & 3A). Following that, the resulting diagrams were analyzed, and it was discovered that the wire resistivity time (without the existence of stray currents and at a temperature of 25 ° C) completed (17 days), which is the longest duration of endure, and the lowest time of resistivity or resistance period (in the existence of an external electric current) is (18 hr.).Impact of (stray currents) at (75 ° C), and this is an indicator of the stray currents with corrosive environment temperatures on the resistance period (withstand duration) in the existence of static stress. The total stimulation increase is 1.9% between corrosion at 75°C and 25°C.

The study of the duration of mechanical resistance to static tensile stress (withstand time) for an aluminum wire that being suffers from the corrosion effect stimulated by stray currents at different temperatures. Test device was designed and produced locally "in advance" in accordance with the specification (ASTM G103 - 97) to create static tensile stress of (1 N) on an aluminum wire of type ASTM (B231/B231M) with particular dimensions and utilized in the transmission of electrical energy, and when the wire is surrounded by a corrosive environment (NaCl solution) (3.5 % NaCl) at three different temperatures (25, 50, and 75 ° C) without any external electrical current causing corrosion; this symbolizes stray currents. Then compare the findings of that example to the results of the same wire's withstand time in the presence of an external electrical current generated by corrosion of type (D.C) by (5V & 3A).Following that, the resulting diagrams were analyzed, and it was discovered that the wire resistivity time (without the existence of stray currents and at a temperature of 25 ° C) completed (17 days), which is the longest duration of endure, and the lowest time of resistivity or resistance period (in the existence of an external electric current) is (18 hr.).Impact of (stray currents) at (75 ° C), and this is an indicator of the stray currents with corrosive environment temperatures on the resistance period (withstand duration) in the existence of static stress. The total stimulation increase is 1.9% between corrosion at 75°C and 25°C.

The aim of present work is to study the erosion –corrosion behavior of aluminum metal composite which consists of the (Al – 12wt % Si) alloy as matrix phase and 10wt% SiC particles as reinforcing phase. Composite material was prepared by stir casting using vortex technique. A general corrosion and erosion-corrosion for the base alloy and the prepared composite were carried out in 3.5wt% NaCl solution as corrosive medium for general corrosion while in erosion-corrosion ,with varying impact angles (0° ,30° ,45° and 90°) in slurry solution ( 1wt%SiO2 sand in 3.5wt% NaCl solution as the erodent). It was found that the general corrosion rate for composite specimen is lower than that of the base alloy (Al-12%Si). In case of erosion-corrosion results, it was found that the weight loss rate or corrosion rate in (gmd) unit at impact angle (0°) is lower than that of other impact angles for the base alloy and composite material.

Erosion–corrosion of Al-Mg-Si aluminum alloy in NaCl–water solutions were studied by weight-loss measurements through an impingement jet system. The effect of sand concentration and fluid impingement angle, were investigated. The sand used is Iraqi silica sand from Al-ardhimah .The result showed that, increasing erosion time, will increase the erosion rate of alloy samples for all sand concentration and impact angels. When the sand concentration is increased the erosion-corrosion rate of alloy samples will increase, and the maximum value of erosion –corrosion rates occur when the impact angle is about( 45◦).The surface morphologies of eroded surface after abrasive water-jetting, show that erosion rather than corrosion, controls the total Erosion-Corrosion rate of Al-Mg-Si alloy in sand-containing NaCl–water solutions.

A study was conducted to demonstrate the effect of mechanical vibrations on the corrosion of steel pipelines for oil (x60, x20) in the corrosive medium is sea water by using the traditional method of weight loss, where the test samples are cut cubic forms and dimensions (10x10x10 mm3). And offered samples to the corrosive solution (sodium chloride 3.5% NaCl) and called the term (sea water) in chemical engineering and corrosion engineering fields. This medium would be static with frequency (0 Hz), and vibrated with a five frequencies (5, 10, 15, 20& 25 Hz) and the amplitude within the range of (0.0013-0.00088m) to be the speed of vibration within the (0.00475-0.022), and for a test time (2hr.). These laboratory vibrations were obtained from the design and manufacture of corrosion presence vibration instrument according to U.S. global standard (ASTM G32). It was found that the speed of vibration increase the corrosion rate of these alloys of (0.00073 gmd) at the speed (0) to (0.00287 gmd) at the speed (0.022) for alloy X20, and (0.00195 gmd) at the speed (0) to (0.00402 gmd) at the speed (0.022) for alloy X60. That is, the highest value for the rate of corrosion is to alloy X60 at the speed of vibration (0.022), followed by corrosion rate of alloy X20 at the same speed. When the speed of vibration was (0), the corrosion rate of alloy X60 is also more of the corrosion rate of alloy X20.

أجریت في ھذا البحث تھیئة لعینات فولاذ أسطوانات الغاز الطبیعي نوع (CK٤٥ (بعملیات التحضیر التقلیدیة ، وتحلیل للتركیب الكیمیائي ، ثم أختبار الصلادة وبعدھا فحوصات التآكل وبحالتین رئیسیتین وھي حالة التآكل العام عندما یكون الوسط الأكال (ماء البحر وحامض الكاربونیك الضعیف) ساكنا" ولمدة أربعة أیام ، والحالة الثانیة ھي حالة التآكل بوجود الأھتزاز المیكانیكي والتي تتضمن حالتین فرعیتین ؛ الأولى حصول حالة التآكل للعینات المھتزه مع الوسط المھتز والثانیة عندما تكون العینات ثابتة والوسط مھتز، ومدة الأختبار الكلي لكل حالة أربع ساعات ،وبعدھا أیجاد فرق الوزن ومعدل التآكل لجمیع حالات التآكل المذكورة بطریقة فرق الوزن التقلیدیة وكذلك دراسة البنیة المجھریة قبل و بعد حالات التآكل . لوحظ أن فرق الوزن و معدل التآكل بلغ أعلى قیمة في الحالة الثانیة من التآكل بوجود الأھتزاز المیكانیكي( العینات ثابتة والوسط الأكال مھتز) ، تلیھا الحالة الأولى من التآكل بوجود الأھتزاز(العینات مھتزة مع الوسط الأكال) ، والأقل قیمة في معدل التآكل وفرق الوزن ھي حالة التآكل العام ( التآكل في الوسط الساكن ). ولوحظ أن البنیة المجھریة لذلك الفولاذ بعد حالة التآكل العام ( في الوسط الأكال الساكن ) أصبحت متآكلة بشكل منتظم والتآكل منتشر على جمیع أجزاء سطح العینة بالتساوي تقریبا" ؛ بینما كانت البنیة المجھریة في حالتي التآكل بوجود الأھتزاز المیكانیكي محتویة على فجوات تآكل غیر منتظمة ومنتشرة بصورة عشوائیة على السطح، وبعمق أكبر وبالأخص الحالة الثانیة (عینة ثابتة في وسط مھتز).