Ultrasonic interfaces

S. I. Rokhlin, M. Hefets, and M. Rosen, An ultrasonic interface-wave method for predicting the strength of adhesive bonds, J. Appl. Phys. 52, 2847 (1981). 

Analysis of Metal-Polymer Boundaries using Ultrasonic Interface Waves... 

Fig. 5. shows six ultrasonic reflection tomograms. Three of these are from the Plexiglas specimen (shown left) and three are from the AlSi-alloy (shown right). The tomograms are reconstructed from reflection data measured across the plane (b), (c) and (e), respectively. The dark regions indicate high reflectivity and represent specimen interfaces and discontinuities. 

These two transducer pairs are activated alternating. For this purpose an ultrasonic instrument is combined with a two channel multiplexer. Figure 8 presents a modified standard instrument USN52 which also implies a modified software. This system performs four measurements per second - alternating the velocity and the thickness are determined. The probe can be scanned over the surface and in every position both, the velocity and the wall thickness are indicated Using the serial interface of the instrument finally a two-dimensional map of velocity or thickness can be generated. 

User Interface This was seen as particularly important, since it has a significant influence on the acceptance of the system by the ultimate user, the ultrasonic technician. 

The control of the airborne sound location system, the coupling monitor and the real-time evaluation of all signals, including the echo indications from the ultrasonic instrument, is carried out on two additional boards in the PC. The graphic user interface (under Windows 95), including online help, enables an easy operation of the system. The evaluation program links all echo indications in real time with the probe position and displays them in a graphic repre-... 

Defect Evaluation in Diffusion Bonding Interface of Dissimilar Metals Using Ultrasonic Testing Method. 

This study detects the defect of the void and the exfoliation in the solid phase diffusion bonding interface of ductile cast iron and stainless steel with a nickel insert metal using ultrasonic testing method, and examine the influence of mutual interference of the reflectional wave both the defect and the interface. 

Therefore, the establishment of the Non-Destructive Inspection technique to understand the presence of the defect on the bonding interface by the ultrasonic wave etc. accurately is demanded. And, the reliability of the product improves further by feeding back accurate ultrasonic wave information obtained here to the manufacturing process. 

This study was in real time measured that the reflective echo height of the bonding interface in the solid phase diffused bonding process of carbon steel and titanium using ultrasonic testing method. As a result, the following were made discernment. 

Nondestructive Testing. Nondestmctive inspection of an explosion-welded composite is almost totally restricted to ultrasonic and visual inspection. Radiographic inspection is appHcable only to special types of composites consisting of two metals having a significant mismatch in density and a large wave pattern in the bond interface (see Nondestructive evaluation). 

Sonic Methods A fixed-point level detector based on sonic-propagation characteristics is available for detection of a liquid-vapor interface. This device uses a piezoelectric transmitter and receiver, separated by a short gap. When the gap is filled with liquid, ultrasonic energy is transmitted across the gap, and the receiver actuates a relay. With a vapor filling the gap, the transmission of ultrasonic energy is insufficient to actuate the receiver. 

As the vast majority of LC separations are carried out by means of gradient-elution RPLC, solvent-elimination RPLC-FUR interfaces suitable for the elimination of aqueous eluent contents are of considerable use. RPLC-FTTR systems based on TSP, PB and ultrasonic nebulisa-tion can handle relatively high flows of aqueous eluents (0.3-1 ml.min 1) and allow the use of conventional-size LC. However, due to diffuse spray characteristics and poor efficiency of analyte transfer to the substrate, their applicability is limited, with moderate (100 ng) to unfavourable (l-10pg) identification limits (mass injected). Better results (0.5-5 ng injected) are obtained with pneumatic and electrospray nebulisers, especially in combination with ZnSe substrates. Pneumatic LC-FI1R interfaces combine rapid solvent elimination with a relatively narrow spray. This allows deposition of analytes in narrow spots, so that FUR transmission microscopy achieves mass sensitivities in the low- or even sub-ng range. The flow-rates that can be handled directly by these systems are 2-50 pLmin-1, which means that micro- or narrow-bore LC (i.d. 0.2-1 mm) has to be applied. 

Bradley M, Grieser F (2002) Emulsion polymerization synthesis of cationic polymer latex in an ultrasonic field. J Colloids Interface Sci 251 (1) 78—84... 

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