PL
 |
EN
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 6

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Content available Reliability Examinations of SAC Lead Free Solder Material
Koncz-Horváth D., Gergely G., Gyökér Z., Gácsi Z.
Archives of Metallurgy and Materials
|
2019
|
Vol. 64, iss. 3
925--930
EN
In this paper the effect of soldering technique and thermal shock test were investigated on SAC 305 solder joints, produced by two different solder method. The solder joints were subjected to different cycle numbers up to 5000 thermal shock tests with two different thermal profiles of –30/+110°C and –40/+125°C. Microstructural properties of the tested joints were examined with the focus on intermetallic layer thickness and crack formation/propagation. Thickness of the scallop shaped Cu6Sn5 intermetallic layer was increased with increasing cycle number for both THRS and multiwave joints, but the thickening was more effective for the THRS joints. Cracks typically formed at the solder alloy/PTH barrel and the solder alloy/pin interfaces and propagated along grain boundaries and precipitations of intermetallic compound.
2
Content available Influence of Ceramic Particles on the Microstructure and Mechanical Properties of SAC305 Lead-Free Soldering Material
Kumar Manoj Pal, Gergely G., Koncz-Horvath D., Gacsi Z.
Archives of Metallurgy and Materials
|
2019
|
Vol. 64, iss. 2
603--606
EN
In this study, silicon carbide (SiC) reinforced lead-free solder (SAC305) was prepared by the powder metallurgy method. In this method SAC305 powder and SiC powder were milled, compressed and sintered to prepare composite solder. The composite solders were characterized by optical and scanning electron microscopy for the microstructural investigation and mechanical test. Addition of 1.5 wt.% and 2 wt.% ceramic reinforcement to the composite increased compressive strengths and microhardness up to 38% and 68% compared to those of the monolithic sample. In addition, the ceramic particles caused an up to 55% decrease in the wetting angle between the substrate and the composite solder and porosity was always increased with increase of SiC particles.
3
Content available Whisker-Like Formations in Sn-3.0Ag-Pb Alloys
Koncz-Horváth D., Gergely G., Gacsi Z.
Archives of Metallurgy and Materials
|
2017
|
Vol. 62, iss. 2B
1027--1031
EN
In this study, different types of whisker-like formations of Sn-3.0Ag based alloy were presented. In the experimental process the amount of Pb element was changed between 1000 and 2000 ppm, and the furnace atmosphere and cooling rate were also modified. The novelty of this work was that whisker-like formations in macro scale size were experienced after an exothermic reaction. The whiskers of larger sizes than general provided opportunities to investigate the microstructure and the concentration nearby the whiskers. In addition, the whisker-like formations from Sn-Ag based bulk material did not only consist of pure tin but tin and silver phases. The whisker-like growth appeared in several forms including hillock, spire and nodule shaped formations in accordance with parameters. It was observed that the compound phases were clustered in many cases mainly at hillocks.
4
Content available Development of Crack Detection Method with 2 Dimensionally Generated 3 Dimensionally Reconstructed Images in THT Solder Joints
Gergely G., Koncz-Horváth D., Weltsch Z., Gacsi Z.
Archives of Metallurgy and Materials
|
2017
|
Vol. 62, iss. 2B
1033--1038
EN
This work represents an interesting development in the detection and interpretation of crack evolution in through hole technology (THT) solder joints, which based on the development of general and common method. Serial sectioning is a useful method because it overcomes the problems associated with traditional two-dimensional metallographic techniques by providing information about (micro)structures in three-dimensions. In our work, serials sectioning with reconstruction method was utilized to visualize the 3D nature of cracks in through hole solder joint. Accurate quantitive analysis of the cracks, such as crack length, position and extension are presented with a help of the developed method: newly defined parameter and serial-cross sectioning method.
5
Content available The Effect Of Void Formation On The Reliability Of ED-XRF Measurements In Lead-Free Reflow Soldering
Koncz-Horváth D., Gergely G., Gacsi Z.
Archives of Metallurgy and Materials
|
2015
|
Vol. 60, iss. 2B
1445--1448
EN
In lead-free reflow soldering, the presence of voids should be taken into account. For this reason, the effect of the applied heating profiles was examined via the characterization of voids in galvanic and immersion Sn coatings. According to EU Directive 2002/95/EC, the screening of Pb element of reflow soldering (i.e. of electrical and electronic equipment) is necessary; and the practical implementation of this measurement is largely affected by the characteristics of the solder (i.e. the presence of voids and the inhomogeneity of the solder). Comparing the results of the above two coating methods, it was found that by chemical coating more voids were formed and the detected lead content was higher than for galvanic Sn. The standard deviation of Ag and Cu concentrations was mainly influenced by the appearance of large compounds in the second case, while with chemical coating, no large compounds were formed due to the elevated number of voids.
6
Content available Microstructure And Mechanical Properties Of Al-WC Composites
Simon A., Lipusz D., Baumli P., Balint P., Kaptay G., Gergely G., Sfikas S., Lekatou A., Karantzalis A., Gacsi Z.
Archives of Metallurgy and Materials
|
2015
|
Vol. 60, iss. 2B
1517--1521
EN
The scope of the research work is the production and characterization of Al matrix composites reinforced with WC ceramic nanoparticles. The synthesis process was powder metallurgy. The produced composites were examined as far as their microstructure and mechanical properties (resistance to wear, micro/macrohardness). Intermetallic phases (Al12W and Al2Cu) were identified in the microstrucutre. Al4C3 was not detected in the composites. Adding more than 5 wt% WC to the aluminum, microhardness and wear resistance exceed the values of Al alloy. Composites having weak interface bond performed the highest wear rate.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.