J Adv Prosthodont.  2010 Dec;2(4):117-121. 10.4047/jap.2010.2.4.117.

Effect of soldering techniques and gap distance on tensile strength of soldered Ni-Cr alloy joint

• Lee SY
• Lee JH

• KMID: 1975185
• DOI: http://doi.org/10.4047/jap.2010.2.4.117

Abstract

PURPOSE
The present study was intended to evaluate the effect of soldering techniques with infrared ray and gas torch under different gap distances (0.3 mm and 0.5 mm) on the tensile strength and surface porosity formation in Ni-Cr base metal alloy.
MATERIALS AND METHODS
Thirty five dumbbell shaped Ni-Cr alloy specimens were prepared and assigned to 5 groups according to the soldering method and the gap distance. For the soldering methods, gas torch (G group) and infrared ray (IR group) were compared and each group was subdivided by corresponding gap distance (0.3 mm: G3 and IR3, 0.5 mm: G5, IR5). Specimens of the experimental groups were sectioned in the middle with a diamond disk and embedded in solder blocks according to the predetermined distance. As a control group, 7 specimens were prepared without sectioning or soldering. After the soldering procedure, a tensile strength test was performed using universal testing machine at a crosshead speed 1 mm/min. The proportions of porosity on the fractured surface were calculated on the images acquired through the scanning electronic microscope.
RESULTS
Every specimen of G3, G5, IR3 and IR5 was fractured on the solder joint area. However, there was no significant difference between the test groups (P > .05). There was a negative correlation between porosity formation and tensile strength in all the specimens in the test groups (P < .05).
CONCLUSION
There was no significant difference in ultimate tensile strength of joints and porosity formations between the gas-oxygen torch soldering and infrared ray soldering technique or between the gap distance of 0.3 mm and 0.5 mm.

Keyword

Ni-Cr alloy; Infrared ray soldering; Gas-oxygen torch soldering; Tensile strength; Joint porosity

MeSH Terms

Alloys
Collodion
Diamond
Electronics
Electrons
Infrared Rays
Joints
Porosity
Tensile Strength
Alloys
Collodion
Diamond

Figure

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  Fig. 1 The specimen made with Ni-Cr alloy.

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  Fig. 2 A Soldering block and embedded specimen.

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  Fig. 3 Infrared ray soldering machine.

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  Fig. 4 SEM image of fracture surface of specimen (×30).

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  Fig. 5 Correlation between tensile strength and porosity.

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