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Bu çalışma kapsamında, gaz jeneratör türbin ve havacılık motor komponentlerinde kullanılan Hastelloy-X ve Inconel 625 süperalaşımlarının, Elektron Işın Kaynağı (EBW), Gaz Tungsten Ark Kaynağı (TIG) ve Plazma Ark Kaynak (PAW) yöntemleri ile birleştirilmesi araştırılmıştır. Kaynaklı bağlantıların mikroyapı ve mekanik özellikleri belirlenmiştir. Bu üç kaynak yöntemi kullanılarak farklı malzemeler başarılı bir şekilde kaynaklanmıştır. Kaynaklı bağlantıların mikroyapı incelemelerinde, malzemelerin termal iletkenliğine göre ısı tesiri altındaki bölgeleri (ITAB) bölgeleri farklılık göstermiştir. En yüksek akma dayanımı ve mikrosertlik değerleri sırası ile 102,88 MPa ve 351 HV0,1 olarak EBW yönteminde elde edilmiştir. In this study, microstructure, microhardness measurements and tensile properties were determined of welded structures used in gas generator turbine and aerospace engine components which were created with Hastelloy-X and Inconel 625 superalloys with three different welding methods Electron Beam Welding (EBW), Gas Tungsten Arc Welding (GTAW), Plasma Arc Welding (PAW). Different materials were successfully welded using these three methods. When the results of the experiments were examined, the ITAB regions differed according to the thermal conductivity of the materials. The highest yield strength and microhardness values were obtained as 102,88 MPa and 351 HV0,1 respectively in EBW method.

ÖZET Çelik malzemelerin kaynağında uygulanan kaynak yöntemlerinden biri olan MAG kaynağında, yapay dış manyetik alan uygulandığında, kaynaklı birleştirmelerin sertlik ve sünekliğindeki değişimleri araştırmak, enine dış manyetik uygulandığında kaynak dikiş formunun nasıl değiştiğini saptamak tez çalışmasının amacını oluşturmaktadır. İlk üç bölümde konuya temel oluşturan tanımlara yer verilmiştir. Dördüncü bölümde kaynak arkının kendi manyetik alam, dış manyetik alanlar hakkında bilgiler, kaynaklı birleştirmeler üzerine makroskopik etkileri, metal transferi ve bu konularda literatürde yapılan çalışmalar aktarılmıştır. Beşinci bölümde deneysel çalışmalar yer almaktadır. Deney malzemeleri ve kullanılan donanım, kaynak koşullan ve parametrelerinin belirlenmesi, çentik darbe ve sertlik numunelerinin hazırlanması ve ölçülmesi akarılmıştır. Değişen manyetik alan değerlerine bağlı olarak nüfuziyet, dikiş genişliği ve dikiş yüksekliği değerlerinin nasıl değiştiği deneysel olarak saptanmıştır. 8 mm kalınlığındaki deney levhaları üzerine yapılan kaynak dikişlerinde, ITAB'de ortalama maksimum sertlik değerinde manyetik alana bağlı olarak bir artış gözlenmiştir. Kullanılan malzemenin Ceş değerine bağlı olarak sertlik değerleri İT AB' de 160 - 200 HV aralığında bulunmuştur. Enine dış manyetik alanların süneklik üzerine önemli bir etkisi olmadığı görülmüştür. Sonuç bölümünde, deneysel çalışmalarda elde edilen değerler, önceki çalışmaların sonuçlan ve çalışmanın geliştirilmesine yönelik öneriler sunulmuştur. Anahtar Kelimeler: MAG kaynağı, süneklik, manyetik alan, ITAB, Ceş ABSTRACT The aim of this study is to investigate whether an external artificial magnetic field applied to MAG arcs improves the ductility and hardness of welded joints. It is also the purpose of the experimental work to determine how the MAG weld bead geometry changes by the application of a transverse magnetic field. The basic definitions of the subject are explained on first three sections. The self magnetic field of welding arc, the information about external magnetic fields, the macroscopical effects on welded joints and the molten metal transfer are mentioned on fourth section. The experimental works are represented on fifth section. The material, welding equipment and welding procedure have been given. The variation of penetration ratio and width-height ratios of weld beam with the increasing magnetic field strength have been determined experimentaly. The hardness in HAZ increased with applied magnetic field on plates 8 mm in thickness. The hardness values in HAZ were found in 160 - 194 HV depending on Ces of the material. It was found that the transverse magnetic fields have no significant effects on ductility. On the result of this study includes the comparison of the ex-experimental works and this one. Keywords: MAG welding, ductility, magnetic field, HAZ, Ces xi 91

n ÖZET Yüksek Lisans Tezi ORTA DAYANIMLI ÇELİKLERİN KAYNAĞINDA ISI TESİRİ ALTINDA KALAN BÖLGENİN MİKROYAPISI VE MEKANİK ÖZELLİKLERİNE MOLİBDENİN ETKİSİ Soner ASLAN Fırat Üniversitesi Fen Bilimleri Enstitüsü Metalürji ve Malzeme Mühendisliği Anabilim Dalı 2002,Sayfa:101 Çeliklerin kaynak kabiliyeti için en önemli gösterge karbon eşdeğeridir. Karbon eşdeğeri içinde yer alan en önemli büyüklüklerden biri de molibden elementi miktarıdır. Bu çalışmada, %0.4, 0.8, 1.4, 1.8 ve 2.2 olmak üzere beş farklı molibden içeriğine sahip düşük karbonlu çelikler, 0.6, 1 ve 2 kJ mm`1 enerji girişleri kullanılarak tozaltı kaynak makinesinde kaynak edilmişlerdir. Kaynağı müteakiben ITAB'ın mikroyapısı, sertliği ve tokluğu bulunmuştur. Ayrıca geliştirilen bilgisayar programı ile tane irileşen bölgenin akma ve çekme dayanımları hesaplanmıştır. Mikroyapı incelemeleri, sertlik ölçümleri ve tokluk testleri sonucunda artan molibden rrıiktarının martenzit ve beynit gibi düşük sıcaklık dönüşüm ürünlerini etkilediği ve bunun ise düşük tokluğa neden olduğu görülmüştür. Anahtar kelimeler: Molibden, İT AB, Mikroyapı, Sertlik, Tokluk m ABSTRACT MSc Thesis EFFECT OF MOLYBDENUM ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF THE HEAT-AFFECT ZONE IN THE WELDING OF MEDIUM-STRENGTH STEELS Soner ASLAN Fırat University Graduate School of Natural and Applied Sciences Department of Metallurgical and Materials Engineering 2002,Page :101 The most important indicator for the weldability of the steel is the carbon equivalent. One of the most important greatnesses which takes place in carbon equivalent is the amount of the molybdenum element. In this study low carbon steels having five different molybdenum contents (0.4, 0.8, 1.4, 1.8 and 2.2 wt.%) were welded using a submerged arc- welding process with heat inputs of 0.6, 1 and 2 kJ mm`1. Following the welding, microstructure, hardness and toughness of heat affected zone (HAZ) were investigated. In addition, tensile and yield strengths of the grain-coarsened area of HAZ were calculated using a developed computer programme. From the results of microstructural investigation, hardness measurements and toughness test it was seen that the increased molybdenum content influenced the formation of lower temperature transformation products, such as martensite and bainite, which resulted in lower toughness. Keyword: Molybdenum, HAZ, Microstructure, Hardness, Toughness 101

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2001, Thesis (PhD) -- İstanbul Technical University, Institute of Science and Technology, 2001, Bu çalışmada, kaynak ısı girdisinin soğuk şekil değiştirmiş S700MC çeliğinin ısıdan etkilenen bölgedeki mekanik özelliklere etkisi incelenmiştir. Araştırmalarda 6 ve 10 mm kalınlıktaki levhalar kullanılmıştır. %5, %10, %15 oranında soğuk şekil değiştirmiş S700MC borlu çelik levhalar 3.5 ve 5 kJ/cm ısı girdisi ile gazaltı kaynağında birleştirilmiştir. Isının tesiri altındaki bölgelerde sertlik, çentik darbe tokluğu, kaynaktan sonraki soğuma hızları ölçülmüştür. Isının tesiri altındaki bölgelerde metallografik incelemeler yapılmış, 100 ve 400 büyütme oranlarında iç yapı fotografları çekilmiştir. İncelemelerde ısıdan iki kez etkilenen bölgelerde ostenit tane sınırlarında borkarbür çökelmesine rastlanılmış ve çökelmenin artan soğuk şekil değiştirme oranı ve kaynak ısı girdisine bağlı olarak arttığı görülmüştür. Artan soğuk şekil değiştirme oranları ve kaynak ısı girdilerinde ısıdan bir kez etkilenen bölgelerde de borkarbür çökelmesi görülmüştür. Sonuç olarak, ısının tesiri altındaki bölgelerde görülen gevrek kırılma sadece soğuk şekil değiştirmiş bölgede kaynak yapılmasının bir sonucu değil aynı zamanda ostenit taneleri sınırında çökelen borkarbür ile de ilgilidir., In is study, the effects of weld heat input on mechanical properties of cold formed S700MC boron steel’s heat affected zone were examined. 6 and 10 mm thick S700MC boron steel plates were used. 5%, 10% and 15% cold formed plates were joined by 3.5 and 5 kJ/cm weld heat input with MAG welding. Hardeness and impact toughness on HAZ were measured. Metallographical examination at 100 and 400 magnification ratio also performed on HAZ. Cooling rates in HAZ , related with cold forming ratoi and weld heat input were measured and plotted. It was found that borocarbide precipitation on prior austenite grain boundaries was more significiant at higher cold forming ratio and weld heat input. Borocarbide precipitaion occured lower temperatures depending on higher cold forming ratio. Consequently, brittle fracture behaviour of cold formed and welded S700MC boron steel’s HAZ realted with not only coarse graining due to welding but also borocarbide precipitation at prior austenite grain boundaries., Doktora, PhD

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ÖZET Bu çalışmanın amacı, çelik malzemelerin kaynağında geniş bir uygulama alanı olan MAG kaynak yönteminde kaynak arkına enine bir dış manyetik alan uygu 1 anıldığında, kaynaklı birleştirmelerin sertlik ve sünek ligindeki değişmeleri araştırmak, aynı zamanda enine dış manyetik alanlara bağlı olarak orta karbonlu alaşımsız imalat çeliği üzerinde dikiş formunun ve nüfuziyetin nasıl değiştiğini saptamaktır. Birinci bölümde, konuyla ilgili çalışmalardan kısaca bahsedilerek konunun önemi üzerinde durulmuştur. İkinci bölümde konunun tanıtımı yapılmıştır. Ark üflemesi, kaynak arkının kendi manyetik alanı, kaynak arkına uygulanan dış manyetik alanlar, dış manyetik alanların etkisi altında arkın sapma sı, kaynaklı birleştirmeler üzerindeki makroskopik etkileri, ark üflemesinin dengelenmesi ve manyetik kontrollü ark kaynağı, metal trans feri konularında litaretürde yapılan çalışmalar aktarılmıştır. Üçüncü bölüm deneysel çalışmaları kapsamaktadır. Bu bölümde, deney malzemelerinin hazırlanması, kaynak koşulları ve parametrelerinin belirlenmesi, çekme ve metallografik numunelerin hazırlanması verilmiştir. Değişen manyetik alan şiddeti değerlerine bağlı olarak nüfuziyet ( h ), dikiş genişliği ( b ) ve dikiş yüksekliği ( c ) değerlerinin nasıl değiştiği deneysel olarak saptanmıştır. 10 ve 15 mm kalınlığındaki deney levhaları üzerine yapılan küt paso dikişlerinde en fazla nufuziyetin 20 gaus civarında olduğu saptanmıştır. Yine aynı levhalarda ITAB ' deki en düşük sertlik değerleri 20 gaus civarın da elde edilmiştir. V ağızlı levhalarla gerçekleştirilen dikişlerde; küt paso dikişlerde olduğu gibi, ITAB 'deki ortalama maksimum sertlik değeri manyetik alan şiddetiyle değişmektedir. En düşük sertlik değerleri 40 gaus 'ta elde edilmiştir. Manyetik alansız yapılan dikişlere göre sertlikteki azalma ITAB 'de % 12 civarında bulunmuştur. Enine dış manyetik alanların süneklik üzerine önemli bir etkisi olmadığı görülmüştür. Sonuç bölümünde elde edilen sonuçlar özetlenmiştir. vı SUMMARY THE EFFECT OF EXTERNAL MAGNETIC FIELDS ON WELD BEAD FORM AND HEAT AFFECTED ZONE IN MAG WELDING PROCESS INTRODUCTION Magnetism has interesting effects on welding arcs. Some of them are detrimental, others benefical. Magnetic fields, whether induced or permanent, interact with the arc current to produce force fields that cause arc deflection commenly called arc blow. Magnetic flux may be self-induced and associated with the arc current, or it may be produced by residual magnetism in the material being welded or by a permanent or generated external source. Since 1960 a great deal of investigations has been carried out on the influence of magnetic fields on.the physical behaviour of the welding arc, the molten droplet transfer, the solidification of the depose ted metal and on the mechanical properties of welding joints Ll - 23], Under certain conditions the arc has a tendency to be forcibly directed away the point of welding, thereby making it difficult to produce a satisfactory weld. This phenomenon, called arc blow, is the result of magnetic disturbances surrounding the welding arc. In gen eral arc blow is the result of two basic factorsC3-5D: (l)The change in direction of current flows as it enters the work and is conducted away toward the ground connection. (2) The asymmetric arrangment of magnetic material around the arc, a condition that normally exists when welding is done on ferrous materials. Although arc blow can not always be eliminated, it can be controlled or reduced to acceptable levels through the knowledge of these two factors. In welding with a.c, their effect on the arc is lessened by eddy currents induced in the work piece. Especially many investigations in the field of arc magnetics were carried out on the gas tungsten-arc welding procesesQ, 8, 9, 13, 21,22J - Some authors investigated how the metal geometry can be changed if a.c. transverse magnetic fields are applied to TIG arcs ' 1,10- They sum up the factors which govern the change in weld gee ornetry as follows: (1) the change in the shape of the heat source from a circular one without the application of the a.c transverse magnetic field, to an elongated or split heat source with the ap plication of the magnetic field. vii(2) The possibility of a partial destruction of the heat transfer be cause noticeable changes in the streaming has occured. (3) The in terruption of heat flow to the work piece because an open circuit condition occured during the welding cycle. As a result of the magnetic field application, the arc deflects either forward or backward depending upon the force directions as described by the fundamental electromagnetic rules. Some authors have attributed the better bead appearance obtained from the forward deflected arc by a transverse magnetic field to the remelting of peaks formed in front rather than at the back of the advancing arc Zl, 8 1. Benefical effects are evident only when the arc is deflect ed forward with respect to the direction of electrode travel. Apply ing an optimum magnetic field to a welding arc provides a possibility in welding techniques at increased speeds and nonmagnetic materials.1. On the other hand, travel speed and rate of shielding gas were reported to have no significant effect on arc deflection L83- V- grooved plate leads to a reduction of the deflection due to the re orientation of the magnetic field lines across the arc gap. Accord ing to Jayarajan and Jackson, the main advantages of magnetic control of welding arc are C9 3 : (1) increased travel speeds at which un dercut-free welds can be made, (2) control over the arc blow effects, and (3) control by the electromagnetic stirring of the weld on the micros tructure. Hiçken and Jackson had also pointed out the same subject (1). They reported that the appearance of the welding arc varies as function of both (a) the magnitude of the applied magnetic field and (b) the type of material upon which the beads are being deposited. They showed that subjecting the welding arc on magnetic and nonmagnetic materials to transverse magnetic fields increases the speed at which undercut-free welds can be made. Gagen and Martynyuk studied the effects of the parameters of longitudinal magnetic fields on the structure and mechanical propert ies of welded joints in gas and oil pipeline welds C2C0. They sug gested that when welds were made with an alternating magnetic field superimposed on the grain size, the welded metal was reduced and the dentritic structure was destroyed. They explained that the improve ment in the mechanical properties was due to the fact that alloying elements were more uniformly distributed in the weld metal when an alternating magnetic field with optimum density and frequency was applied. Drozdov and Rubstov introduced the generalized quality coeffi cient which made it possible to determine the critical magnetic in duction above which weld quality begins to decrease C2ÎJ. They found that the lowest resistance to the effect of magnetic fields was exhi bited by manual arc welding, and the highest resistance by automatic submerged arc welding. Some authors determined that the effect of magnetic fields was more evident in welding in overhead and vertical positions C 21 3. The aim of this study was to investigate whether a transverse magnetic field applied to MAG arcs improves the ductility and hard ness of welded joints. It was also the porpose of the experimental work to determine how the MAG weld bead geometry changes by the ap plication of a transverse magnetic field. vinEXPERIMENTAL WORK 1. Material and welding equipment Two types of medium-carbon steels were used. Their chemical analysis are shown in Table 3-1. Type DIN 8559-SG2 wire (1.0 and 1.2 mm diameter, 0.1 % C ) was used as filler metal. The welding equip ment used was a self-adjusting automatic MAG welding machine. 2. Measurement and application of the magnetic field The transverse magnetic field applied to the welding arc zone was produced by a d.c electromagnet. A general scheme of this cir cuit is shown in figure 3-2. The arrangment of the welding torch, magnetic poles and the test plates is shown in figure 3-3. The magnetizing current was supplied through a variable transformer and then rectified. The direction of flux lines could be changed by re versing the magnetizing current. A gaussmeter with a transverse Hall probe was used to measure the magnetic field. This measured d.c. magnetic field strength in the range of 0.1 gauss full scale to 1000 gauss full scale in 12 ranges. Measurements of the magnetic field strength were made along the weld axis and over 3 mm on the plate. The Hall probe was kept parallel to the magnetic flux lines during the measurements and the maximum reading was recorded. All measurements were made before welding. 3. Welding procedure Bead on plate and single V-grooved plate welds were made. The shielding gas was pure C02- Direct current (electrode positive) was used for making all the welds. In all the cases, the magnetic field applied to the arc zone was so that it deflected the arc forward with respect to the direction of travel. The welding conditions are list ed in Table 3-2. In the case of the V-grooved plate weld, the specimen was cooled to room temperature after each pass and before another pass was made. For each measurement of magnetic field strength value five plates were used. Two transverse cylindirical tensile weld specimens with a diam eter of 6 mm and one hardness specimens were prepared for each weld. For the bead on plate weld bead dimensions and hardness values were measured in function of the magnetic field strength. Hardness measurements were made at a distance of 1 mm below the base metal surface and along the weld axis using a vickers hardness tester with a load of 500 gr. and intervals of o.5 mm. RESULTS AND DISCUSSION 1. Weld metal dimensions (for bead on plate welds) For each value of magnetic field strength measured, weld bead dimensions for two different welding currents (160 amp. and 220 amp.) are shown in figure 3-15. Penetration was found to increase slightly up to 20 gauss, thereafter the penetration decreased quickly. IXFirstly, an increase in magnetic field strength and an increase the cross section of weld metal was observed as shown in figure 3-18 and 3-19. At the beginning an increase in magnetic field strength re sulted in an increase in net energy input (Enet) or in other words an increase in the heat transfer efficiency (f^) expressed by Enet = f^.U.I/v. It is possible to explain this phenomenon by the contrac tion of arc and increasing heat input as a result of low external transverse magnetic field strength. Thus, weld energy per unit bead length increases in constant welding conditions (U, I, v = Constant). On the other hand when magnetic field strength was increased up 40 gauss, arc blow became effective. Then, weld energy per unit length Enet t i -e. the heat transfer efficiency f]_ probably decreased. This phenomenon and metal spatter which takes place in higher magnetic field strengths resulted in a decrease in cross section of weld metal. Both the width of heat affected zone (HAZ) and the cross section of HAZ continously increased by increasing magnetic field strength. This increase can probably be related to local preheating effect caus ed by arc blow, although Enet/ net energy input decreased. 2. The hardness distribution and changes in HAZ depending on the magnetic field strengths. 2-1. For bead on plate welds. For 15 mm thickness and 160 amp. the minimum hardness values in HAZ were found at 40 gauss t When the external magnetic field was not applied, and with a measured residual magnetism of only 5 gauss, the average of maximum hardness was 527 vickers. When an external trans verse magnetic field was applied hardness values first decreased up to a magnetic field of 40 gauss; above 40 gauss, the hardness values again increased. Optimum magnetic field strength was obtained at 40 gauss (Figure 3-25 and 3-22 ). For same specimens the measurement hardness along the weld axis are shown in figure 3-26 and 3-28. Similarly, for 10 mm thickness and 220 amp. the hardness values in HAZ were found to be parallel to the above values. The graphs con cerning these shown in figure 3-29,...,31). 2-2. Single V-grooved plate welds. When the external transverse magnetic field was not applied, the average of maximum hardness was 345 vickers, when an external trans verse magnetic field was applied hardness values first decreased up to a magnetic field of 40 gauss. Above 40 gauss, the hardnes values again increased. Optimum magnetic field strength was obtained at 40 gauss. The hardness value was 305 vickers and the hardness gain was about 12 percent at 40 gauss ( Figure 3-33 and. 3 - 34 ). It can be sum up the factors which governs the change in hard ness depending on the magnetic field strengths, for bead on plate welds. Firstly, an increase in the cross section of weld metal and a decrease in maximum hardness values measured in HAZ were obtained by increased magnetic field strength. At the beginning, an increase in xmagnetic field strength resulted in an increase in net energy input ( Enet ) or in other words an increase in the heat transfer efficiency ( ±i ) expressed by Enet = ( fi-U.I ) /v. It is possible to explain this phenomenon by the contraction of arc and increasing heat input as a result of low external transverse magnetic field strength. On the other hand, when magnetic field strength was increased the cooling rate decreased since it is inverse proportional to the energy input. Thus, maximum hardness values measured in HAZ also decreased. On the other hand magnetic field strength was increased up to 40 gauss, arc blow became effective. Then, weld energy per unit length Enet, i.e. the heat transfer efficiency f ]_ probably decreased. This phenomenon and metal spatter which takes place in higher mag netic field strength resulted in a decrease in cross section of weld metal. The cooling rate in HAZ increased due to a decrease in Enet- Thus, maximum hardness values obtained in HAZ increased. As a matter of fact, for bead on plate welds both on plates 10 mm and 15 mm in thickness maximum hardness values measured in HAZ de creased after 40 gauss ( Figure 3 - 27, 3-28, 3-31 and 3 - 32). Both the width of heat affected zone ( HAZ ) and the cross sec tion of HAZ continously increased by increasing magnetic field strength. This increase.can probably be related to local preheating effect caused by arc blow, although Enet> net energy input decreased. Because the preheating caused by arc blow was local it did not change the initial temperature To/ of the workpiece. As a result, preheating did not change the cooling rate. 3. The relation between ductility and applied external trans verse magnetic field strength. Computed values of elongation and reduction of area against the magnetic field strength are shown in figure 3-35 and listed in Table 3-6. Tensile strength and yield strength are given in Table 3-7. Optimum magnetic field strength was determined to be 40 gauss. At the value of 40 gauss both elongation and reduction of area were about 3.3 and 11.4 percent respectively. Tensile strength and yield strength seem not to be affected by the magnetic field. All tensile specimens broke in the weld joint with a ductile failure. CONCLUSIONS 1. In case of bead on plate welds on the plate of 15 mm and 10 mm thickness; 1.1. Average maximum hardness values in HAZ changed with exter nal magnetic field strengths. The lowest hardness values in HAZ was obtained at the magnetic field value of 20 gauss. 1.2. In general, penetration decreased with increased magnetic field strength, however a slight increase was found at 20 gauss ( about 5 percent ). xi1.3. The deep penetration ( h / b ) and surface penetration ( c / b ) ratios decreased with increased magnetic field strength. Especially, this situation is important for surfacing and in welding of thin plates. 2. In case of V - grooved plate welds, fallowing conclusions obtained; 2.1. The lowest hardness values in HAZ was obtained at the magnetic field value of 40 gauss. 2.2. The hardness in HAZ decreased about 12 percent compared to those found without applied magnetic field. 2.3. The transverse magnetic field has no significant effect on the ductility. However, in 40 gauss, slight increase in ductility was found ( the elongation and reduction of area were about 3.3 and 11.4 percent respectively). xn 85

Makale, İtab lüğatta bir kimseyi yaptığı bir işten dolayı kınamaktır. Kur'an'da geçen itab ayetlerinin manası' ise şudur: Kur'an-ı Kerim'in mahdut birkaç ayetinde Hz. Peygamber (sav) in görüşünde en iyi olanı terk ettiği tescil edilmiş ve bu sebeple Allah tarafından kendisine itab tevcih edilmiştir. Şüphesiz insaf sahibi olan herkes, Kur'an'ın Allah kelamı olduğuna kesinlikle hükmeder. Eğer Kur'an Hz. Muhammed {sav) in sözü olsaydı; bu itabı kendi şahsı hakkında tescil ve ilan etmezdi.