Weld-bonding

The fixing of the joined parts is weaker than in welding, bonding, and screw joining... 

Transition joints are used to join dissimilar metals where flanged, screwed, or threaded connections are not practical. They are used when fusion welding of two dissimilar metals forms interfaces that are deficient in mechanical strength and the ability to keep the system leak-tight. Transition joints consist of a bimetallic composite, a stainless steel, and a particular kind of aluminum bonded together by some proprietary process. Some of the types in use throughout the cryogenic industry are friction- or inertia-welded bond, roll-bonded joint, explosion-bonded joint, and braze-bonded joint. 

Solvent-Based Adhesives—In these the adhesive flows because it is dissolved in an appropriate solvent, and solidification occurs on evaporation of the solvent. Good bonds are usually formed if the solvent attacks or actually dissolves some of the plastic adherend to produce a solvent-welded bond. 

Darwish, S. M. H., and Ghanya, A., Critical Assessment of Weld-Bonded Technologies, Journal of Materials Processing Technology, vol. 105, 2000, pp. 221-229. 

Chang, B. H., et al., A Study on the Role of Adhesive in Weld-Bonded Joints, Welding Research Supplement, August 1999, pp. 275s-279s. 

Tissue repair wound repair tissue welding/bonding... 

Previous studies [1,2] examined the welded dowel surface after pull-out from the substrate. In this work, the SEM study focused on the welded-joints (Eig. 6(a-d)). Figure 6(a) shows a poorly welded joint between the dowel inserted in the hole (left side) and the maple substrate (right side), whereas Fig. 6(b) presents a well-welded bond between the dowel (right side) and the maple substrate (left side). When examining in more details the micrograph for maple, one can see the absence of visible cracks at the interface between the dowel and the substrate, as... 

For film adhesives, ultrasonic welding (112) at a frequency of approximately 15,000 kHz can be used instead of weld-bonding. The subsequent curing can also be completed in a regular oven. This technique has been applied to small... 

Beemer, R.D., Introduction to weld bonding. SAMPE Quart, 5(1) 37 1, October 1973. 

Bonder, B.B., Preparation of aluminum alloy surfaces for sport weld bonding. Proceedings of the 7th National SAMPE Technical Conference, Vol. 7, Albuquerque, New Mexico, pp. 374-385. 

Polycarbonate parts having thickness of at least 40 mils can be successfully hot gas welded. Bond strengths in excess of 70 percent of the parent resin have been achieved. Equipment should be used capable of providing gas temperature of 315 to 648°C. As prescribed for the heated tool process, it is important to adequately predry (120°C) both the polycarbonate parts and welding rods. The bonding process should occur within minutes of removing the parts from the predrying oven. 

Polystyrene modified polyphenylene oxide (PPO) or Noryl can be hot plate welded at 260 to 288°C and 20 to 30 s contact time. Unmodified PPO can be welded at hot plate temperatures of 343°C. Excellent spin welded bonds are possible with modified polyphenylene oxide (PPO), because the low thermal conductivity of the resin prevents heat dissipation from the bonding surfaces. Typical spin welding conditions are rotational speed of 40 to 50 ft/min and a pressure of 300 to 400 psi. Spin time should be sufficient to ensure molten surfaces. 

In contrast to the aerospace industry (see Aerospace applications), conditions prevailing in automobile manufacture dictate that pre-treatments (see Pre-treatment of aluminium) should have short process times and be tolerant of production variables. The surfaces produced should retain adequate bonding properties during extended storage under poorly controlled conditions. The surface may need to be sufficiently conductive to permit weld-bonding techniques. Pre-treatments applied at the coil stage must be compatible with mill oils and press lubricants, and withstand mechanical deformation in the press. 

The above approach has not, to date, been extended to include steel, although considerable effort is expended in its pre-treatment prior to painting. The current practice is to weld bond oil steel using single-part epoxy adhesives curing during the first (electrocoat)... 

Box team sections have been extensively employed in the evaluation of bonding and weld-bonding systems for possible application in the transport industry. Of particular value in section design and the optimization of spot-weld distribution, they provide useful indications of initial performance in more relevant geometries. 

Adhesives welding bonding fastening welding welding... 

Polycarbonate parts with thicknesses of at least 40 mils can be successfully hot-gas-welded. Bond strengths in excess of 70% of the... 

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