Welded joints corrosion phenomena for some kinds of stainless steels and nickel alloy was studied in
polluted phosphoric acid 37.7%H3Po4 using electrochemical techniques like Tafel polarization. Corrosion
rate of base metal and weld metal had calcu
lated & compared among these alloys.
Laboratory Test results showed the change in both corrosion rate and corrosion current densities (Icorr)
for tested alloys, and there is a clear difference between base metal and weld metal in most of tested alloys
, which lead to high corrosion rates of welded joint, and change in its properties then gets out of service in
some service conditions. The stainless steel 904L has low corrosion rates and low difference in corrosion
rates between base metal and weld metal, so it may be the most suitable alloy, among all the studied
alloys, for exploitation in polluted phosphoric acid 37.7%H3Po4 produced at the General Fertilizer
Company in Homs city.
This study includes an experimental work to determine the effect of dilution on
Hardfacing welding of clinker hammer crusher. In this work, samples have been prepared
from the same metal type of hammer’s, of which is X120Mn12. Then the samples had
been hardfaced using deferent kind of hardfacing Shielded Metal Arc Welding electrodes,
and using deferent welding parameters (current, polarity), the calculation and measuring of
dilution had done and then performed the hardness tests, wear tests, and their relation with
dilution.
This study showed that the reduction of heat input decreases dilution as the hardness
of hardfaced samples increases and wear decreases.
Direct current electrode positive (DCEP) increase dilution as the hardness of
hardfaced samples decreases and wear increases, but the quality of the welding became
better. Results showed that percentage of chromium and carbon in electrodes have positive
effect on hardness.
Design of experiments (DOE)
had been used in the study, and the results had been evaluated by the
surface response method. The results showed that the welding
current is the main parameter by its effect on the mechanical studied
properties and the parameters values which give the best responses
had been determined.
يهدف هذا البحث الى دراسة تأثير متغيرات اللحام على الدخل الحراري و المردود الحراري و على الدورة
الحرارية عند لحام صفائح من الفولاذ المقاوم للصدأ.
تم في هذا البحث التعرف على مفاهيم الدخل الحراري و الدورة الحرارية و الاطلاع على النماذج التي
توصف انتق
ال الحرارة في أثناء عملية اللحام.
تم اجراء دراسة على طرائق تحصيل الدخل الحراري شملت المسعرات المائية (البسيط، و المصعدي
التدفقي، و المصعدي المغمور) و قد تبين من نتائج القياس التي تم الحصول عليها أن المسعر المائي
المصعدي المغمور هو النسب في قراءة قيمة الدخل الحراري.
