سید اختر علی تلہری
سید اختر علی صاحب فن شاعر اور نکتہ سنج ادیب تھے، اردو اور فارسی زبان و ادب پر استادانہ نظر تھی، عربی اور انگریزی سے بھی واقف تھے، ساری عمر درس و تدریس اور تالیف و تصنیف میں گذری، ان کے تلامذہ کا دائرہ بہت وسیع ہے ان کی تربیت نے بہت سے شاعر و ادیب پیدا کردیے، ان کا کلام اور مضامین رسالوں میں نکلتے رہتے تھے، معارف میں بھی ان کی غزلیں شائع ہوتی تھیں، عرصہ ہوا معارف میں ہندوستان کے عربی شعرا پر ایک مبسوط مضمون شائع ہوا تھا، اتفاق سے اس میں کسی شیعہ شاعر کا ذکر نہ تھا، تلہری صاحب نے مجھ کو شکایت کا خط لکھا میں نے جواب دیا کہ اس میں میرا قصور نہیں ہے مضمون جس شکل میں آیا تھا میں نے شائع کردیا، اگر آپ شیعہ شعرا پر لکھ بھیجیں تو اس کو بھی شائع کردیا جائے گا، چنانچہ یہ مضمون انھوں نے لکھ کر بھیجا اور وہ شائع ہوا، مضامین کے علاوہ مستقل علمی و ادبی تصانیف بھی ان کی یاد گار ہیں، آج کل شاعروں اور ادیبوں کی کمی نہیں، ان کی تعداد روز افزوں ہے اس سے نظم و نثر دونوں کا دامن بہت وسیع ہوگیا ہے لیکن فنی مہارت اور علمی و ادبی بصیرت مفقود ہوتی جاتی ہے۔ تلہری مرحوم کی وفات سے ایک صاحبِ علم و ادب اور صاحبِ فن شاعر اٹھ گیا۔ اﷲ تعالیٰ ان کی مغفرت فرمائے۔ (شاہ معین الدین ندوی، مئی ۱۹۷۱ء)
Allah the elevated bestowed on prophet Muhammad SAW two basic sources of guidance for Muslim Ummah, The holy Quran and Hadith. Due to this significance of Hadith, Muslims have invented more than five hundred sciences related to Hadith. One of these sciences is Ilm Garb ul Hadith. Sheikh Moaamer bin muthana was the first scholar who has written a book on this topic. From then on Muslim scholars have researched a lot in this regard. Dozens of scholars spent their time and wealth on it. According to the author of Moaajm ul mua’ajam more than 90 books on the topic have been published but eight of them gained much publicity and famous hood among them. Abu Ubaida, Abu Adnan, Abu Ubaida Qasim bin Salam, Ibrahim bin Ishaq Al Harbi, Abu Ubaida Ahmed bin Muhammad Alhervi, Ibn Jauzi, Muhammad bin Atheer Aljazree, Zemakhsharee. The following article consists of a brief introduction of Ilm Gharib ul Hadith along with a brief history of research about it. Then the eight famous books on Gharib ul Hadith and there way of research are examined in brief along with examples. At last a comparative study of the work done by these eight scholars is given in order to explore the differences and similarities among them.
The use of welding processes, especially for joining of aerospace alloys has gained a significant importance in the recent years. This is owing to the enhanced joint efficiency, increased sealing ability and reduced weight of the welded structures as compared to riveted structures. Moreover, the modern trend in aerospace industry has shifted towards the use of titanium alloys, due to their high strength to weight ratio and good corrosion resistance. This work is focused on the welding of the well-known α titanium alloy Ti-5Al-2.5Sn, which haslow cost alloying elements as compared to the mostly widely used Ti-6Al-4V alloy, has a good weldability and is also more suitable for high temperature aerospace applications. Tungsten inert gas (TIG), laser beam welding (LBW) and electron beam welding (EBW) are the mostly used welding methods for titanium alloys. As compared to TIG welding, LBW and EBW are always the preferred welding methods due to low heat input and deep penetration characteristics. However, TIG welding is mostly employed industrially due to significantly less capital cost and ease of automation due to reduced equipment size. A number of gaps were identified in the open literature related to the welding of Ti-5Al-2.5Sn alloy. Firstly, few studies are available in the public domain related specifically to the welding of Ti-5Al-2.5Sn alloy using TIG, LBW and EBW. Moreover, the reported work related to comparison of TIG, LBW and EBW of other titanium alloys is limited and there is a need of in-depth, comprehensive comparison of these welding processes in terms of microstructure, mechanical properties and residual stresses in the welded structures. The opportunities available for parametric analysis of LBW process in titanium alloys and optimization of the pulsed TIG welding process for titanium alloys especially Ti-5Al-2.5Sn alloy have not been explored to full potential. The present work aims mainly at improving the pulsed TIG (P-TIG) welding process for 1.6 mm thick Ti-5Al-2.5Sn alloy sheet so that resultant microstructure, mechanical properties and residual stresses are comparable to that of pulsed LBW (P-LBW) and EBW weldments. Microstructure, oxide contents and microhardness of fusion zone, HAZ width, weld zone strength, tensile residual stresses and plate deformations were measured to compare the performance of the weldments. P-LBW was found to be most suitable in terms of these performance attributes of TI-5Al-2.5Sn welds due to low heat input which led to a complete martensitic transformation in the FZ. The absence of shielding gas due to vacuum environment in EBW was beneficial in terms of increasing the joint quality (low oxide contents). However, an increased width of heat affected zone (HAZ) and partial α’ martensitic transformation in FZ of EBW was observed as compared to P-LBW. High heat input and much wide heat source in P-TIG led to coarse microstructure and partial martensitic transformation in FZ resulting in increase of FZ and HAZ width, plate deformations and tensile residual stresses and a reduction in FZ microhardness and weld zone strength. The optimization of P-TIG welding was performed using Box-Behnken design of experiments in which a mathematical was developed to establish the relation between the welding input factors (peak current, background current and welding speed) and output responses (FZ width, HAZ width, FZ grain size, ultimate tensile strength, notch tensile and impact strength, and elongation, longitudinal and transverse residual stresses). The dependence of output responses on the inputs of P-TIG welding and its physical significance in the context of microstructure was discussed in detail. Optimization was performed through different criteria and a multi-response optimization was suggested to maximize the joint strength, impact properties and minimize the residual stresses. Results were experimentally validated and the range of welding input parameters were recommended through overlay plots for industrial application.