Schlieren interferometry is found to be an alternative tool for temperature measurement during thermoplastic laser welding with regard to methods based on thermocouples or optical pyrometers. In fact, these techniques are not easily applied when materials to be processed have reduced thickness, negligible heat conduction, and low emissivity, as is the case of welding high-density polyethylene f...

The in-process monitoring and real-time control of the penetration depth during laser welding is evaluated. An optical collimator collects the optical emission for measurement with a fast spectrometer. The sensor data are used to calculate the electron temperature and subsequently to determine the weld quality of overlap welds in AISI 304 stainless steel sheets performed both with CW Nd:YAG and...

BACKGROUND AND OBJECTIVES The success of laser tissue welding or soldering depends on optimal laser settings, solder material, and tissue type and geometry. To develop a practical laser welding technique for ureteral repair, an intraluminal albumin stent was designed to enhance the welding effects on ureteral end to end anastomosis. STUDY DESIGN/MATERIALS AND METHODS In vitro porcine ureters ...

In general, it is desirable to finish the weld quickly, before a large volume of surrounding metal heats up and expands. The welding process used, type, welding current and speed of travel, thus, affect the degree of shrinkage and distortion of a weldment. The use of mechanized welding equipment reduces welding time, metal affected zone and consequently distortion. This article helps to define ...

Precision components or sensors exposed to corrosive conditions, or required to have extreme performance characteristics, are sealed hermetically into special packages. Epoxy glueing, resistance welding, soldering, electron-beam welding, and laser welding are several of the techniques available for sealing these packages. The disadvantage in the use of epoxies is that they do not create a herme...

Monitoring systems for the laser keyhole welding process of aluminium Tailor Welded Blanks, are in many cases vital to ensure a certain weld quality. Especially process visualization with camera based systems gives a lot of insight. Although for steel it has already been demonstrated that images can be obtained in real-time from the laser welding process using these cameras based on silicon chi...

OBJECTIVE To compare the deflection load characteristics of homogeneous and heterogeneous joints made by laser welding using various types of orthodontic wires. MATERIALS AND METHODS Four kinds of straight orthodontic rectangular wires (0.017 inch × 0.025 inch) were used: stainless-steel (SS), cobalt-chromium-nickel (Co-Cr-Ni), beta-titanium alloy (β-Ti), and nickel-titanium (Ni-Ti). Homogene...

In order to automatically control the quality of the welding process, this paper concentrates on the problem of three dimensional surface reconstructions for the welding pool. As the relationships between size and shape of the welding pool are very complex and nonlinear, we utilize the fuzzy neural network to solve the proposed problem. In the fuzzy neural network, the input vector with 48 dime...