EXPLOSIVE WELDING THEORY AND PRACTICE СВАРКА ВЗРЫВОМ теория

EXPLOSIVE WELDING: THEORY AND PRACTICE СВАРКА ВЗРЫВОМ: теория и практика L. B. Pervukhin EPNM– 2010

The analysis of defects arising in the course of industrial production of bimetal by explosion welding Change of joint durability on the sample length. 250 Distribution of joint durability to tearing off on length of sheet. «свищи» , непровары вздутие Defects in clad sheet: faulty fusion at the initial stages, worm -holes, local tear-out of clad material

Class on continuity of layers joint ГОСТ 10885 -85 The defect area sm 2 Marks of steels, the size (mm) Defect kind 09 Г 2 С+Тр316 Тi 23(20+3)х1400 х5900 09 Г 2 С+Тр321 45(41+4)х1400 х5900 Quantity of sheets In total The defective 10 -50 0 0 Local tear-out I Faulty fusion at the initial stages 5 1 0 3 0 0 Worm-holes II 20 -100 Faulty fusion at the initial stages Local tear-out Worm-holes III 50 -250 Faulty fusion at the initial stages Local tear-out Worm-holes 51 99 7 1 51 4 2 99 5 2 4 3

The scheme of joint formation

Method of "traps". The surface of a trap after welding of the Ti+Steel on air. The covering from a mix oxygen the titanium is observed on a surface. Fe, Fe 3 N The surface of traps after welding of the titan with a steel in argon is absent a covering. In this photo machining traces are visible.

The scheme of calculation of shock-compressed gas area ahead of a contact point υ υ Vk Two problems are in common solved: -Problems about the moved piston, define of gas parameters for shockwave; -Problems about flow out velocity of gas from a welding gap; Vk – the contact point velocity ; Р 0 – atmospheric pressure; Р 1 – pressure in the shock-compressed gas υ - flow out velocity of gas from a welding gap; l – length of shock-compressed gas area mgr - The grasped weight of air mex - The expiring weight of air

Plastic deformation in the process of joint formation. Activation time of shock-compressed gas area is 0. 9 · 10 -4 s Activation time of plastic deformation area is 1 · 10 -7 s p>>σд P – давление σд – динамический предел прочности ε= l / l 0 l –длина линии соединения, l 0 – длина проекции

Sequence of joint formation At pressure welding 1. Formation of physical contact 2. Surface activation 3. Volumetric interaction Our suggestion 1. Cleaning and surface activation of welded plates occurs due to the interaction of shock-compressed gas and plasma stream formed at high-speed flow and plastic deformation at formation of a deformation hillock in the localised zone the limited isobar of high pressures 2. Formation of physical contact and joint in contact point 3. Volume interaction with joint formation and plastic deformation behind a contact point

Technological bases of industrial manufacture • Choice of the scheme of welding with the account of properties of welded materials, features of narrow sides deformation and scraps of plating sheet • Rational technology of surfaces preparation of initial materials and assemblage of packages • Use as explosive mixtures of microporous ammoniumnitrate + diesel oil. • Minimising of influence of external factors for the account of performance of all operations on explosion welding preparation in shop. (On range the apportion of explosive is made only. ) • Quality assurance at all stages of manufacture of bimetal.

Results of manufacture of bimetal on advanced technology. Marks of steels, the size (mm) Class on The continuity defect Defect kind 09 Г 2 С+Тр316 Тi 09 Г 2 С+Тр321 of layers 23(20+3)х1400 х5900 45(41+4)х1400 х5900 area joint sm 2 Quantity of sheets ГОСТ 10885 -85 In total The defective II 20 -100 0 3 1 Worm-holes 10 -50 0 Local tear-out I Faulty fusion at the initial stages 1 0 Faulty fusion at the initial stages 0 0 Local tear-out 208 0 21 0 Worm-holes III 50 -250 0 0 Faulty fusion at the initial stages 0 0 Local tear-out 0 0 Worm-holes 0 0

Ready bimetal After explosion welding After heat treatment and editing

Industrial production of bimetals by explosion welding in Moscow region provides with: • The high quality confirmed with the certificate at a competitive price; • All-year industrial production; • Deadlines of performance of works from reception of the order before delivery; • Maintenance on request of the customer of a full cycle of manufacture, including heat treatment, furnish and carrying out of tests for conformity to requirements of standards and specifications. Co-production «Bitrub International Ltd » and FKP NII «Geodeziya»

Quality of clad metals is provided with: On-receipt inspection of raw materials • Manufacture technology • Control system of technological parameters during all manufacturing stages Finished clad metals are subjected to the next modes of inspection: • Ultrasonic checkout of joint continuity • Checkout of joint tearing strength, shearing strength and bending strength • Ultrasonic and metallographic checkout of clad layer thickness • Checkout of deflection from flat surface accuracy • Checkout of mechanical properties of base layer according to Customer’s requirements

The basic documents regulating quality of the bimetal received by explosion welding 1. 2. 3. ГОСТ 10885 -85 ТУ 27. 32. 09. 010 -2005 «Two-layer corrosion-resistant sheet steel produced by explosion welding » ТУ 27. 81. 09. 009 -2005 «Two-layer feedstocks Steel + Titanium obtained by explosion welding » Foreign analogues 1. NC 501 General Specificacion(Франция) 2. AD Merkblatt W 8, Iuli 1987, спецификация 1264 от 4. 85.