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Wettability and Hardness Investigation of Nickel-Coated Precipitated Calcium Carbonate Sn-9Zn Composite Solder

Keong L.W., Zainal Farah Farhana, Kasmuin M.Z., Mohamad A.A., Nazeri Muhammad Firdaus Mohd, Nabiałek Marcin, Jeż Bartłomiej

Archives of Metallurgy and Materials

2023

Vol. 68, iss. 3

1035--1040

To fabricate a lead-free solder with better properties, a surface-modified precipitate calcium carbonate (PCC) was added as a reinforcement phase to tin-zinc (Sn-9Zn) solder. The surface modification of PCC was done by using electroless plating to deposit nickel (Ni) layer on the PCC. Based on microstructure analysis, a thin layer of Ni was detected on the reinforcement particle, indicating the Ni-coated PCC was successfully formed. Next, composite solder of Sn-9Zn-xNi-coated PCC (x = 0, 0.25, 0.50, 1.00 wt.%) was prepared. The morphology and phase changes of the composite solder were evaluated by using optical microscope and X-ray diffraction (XRD). Significant refinement on the grain size of Zn was seen with the additions of Ni-coated PCC, with a new phase of Ni3Sn4 was detected along with the phases of Sn and Zn. The wettability of Sn-9Zn was also improved with the presence of Ni-coated PCC, where the wetting angle decreased from 28.3° to 19.4-23.2°. Brinell hardness test revealed up to 27.9% increase in hardness for the composite solder than the pristine Sn-9Zn solder. This phenomenon contributed by the increased in dislocation resistance through Zener pinning effect and Zn grain refinement within the composite solder which enhanced the overall properties of the composite solder.

Precipitated calcium carbonate production, synthesis and properties

Erdogan N., Eken H. A.

Physicochemical Problems of Mineral Processing

2017

Vol. 53, iss. 1

57--68

Calcium carbonate (CaCO3) is the most widely used filler material in paper, paint, plastic, food, ceramic, cosmetic, medicine and other industries. In the present paper, precipitated calcium carbonate (PCC) has been produced from waste marble powder (WMP) by the Calcination-Dissolution-Precipitation (CDP) method. Calcination, dissolution and precipitation experiments were carried out under various conditions including : calcination temperature (800, 850, 900, 950 and 1000 °C), dissolution time (2.5, 5.0, 7.5 and 10.0 min) and precipitation time (2.5, 5.0, 7.5, 10.0, 12.5 and 15.0 min). Then, XRF, XRD, SEM, particle size, whiteness, brightness and yellowness analyses were performed for the characterization of the produced PCC materials. The analyses showed that the precipitate was mainly micrometer-sized (d50 = 1.682 μm) rhombohedral calcium carbonate crystals with 54.5% CaO. The whiteness, brightness and yellowness tests of the precipitates, conducted by Datacolor Elrepho 450x spectrometer, were determined to be 91.28, 98.2 and 1.99%, respectively. It was finally concluded that the produced PCC material reasonably meets Turkish Standards (TS 11653/1995) and can be used in paper industry.

Nanokompozyty PVC/CaCO3 otrzymywane metodą polimeryzacji suspensyjnej chlorku winylu

Abramowicz A., Obłój-Muzaj M.

Zeszyty Naukowe Politechniki Poznańskiej. Budowa Maszyn i Zarządzanie Produkcją

2007

Nr 4

7-13

Nanokompozyty PVC u udziałem komercyjnych nanonapełniaczy Soca! U! (strącany węglan wapnia, niemodyfikowany) oraz Socal U1S2 (strącany węglan wapnia o powierzchni powlekanej kwasem stearynowym), były otrzymywane w suspensyjnej polimeryzacji chlorku winylu. Struktury otrzymanych próbek obserwowano za pomocą SEM (przełomy kruche) oraz SEM HR (przekroje poprzeczne). Analizy wykazały dobre zdyspergowanie nanonapelniacza w PVC oraz dobrą adhezje miedzy nanonapełniaczem a matrycą polimerową. Porównanie wybranych właściwości mechanicznych próbek PVC/SocalUl i PVC/Socal U1S2 wykazało nieznacznie mniejsze: wytrzymałość na rozciąganie(2%) i wydłużenie względne przy zerwaniu (6%) a znacznie lepszą udarność (o ok. 30%)nanokompozytu PVC/SocalUlS2.

Nanocomposites PVC/CaCO3-ncat and PVC/CaCO3 modified with stearin acid were prepared in suspension polymerisation of viny! chloride. SEM of brittle fractures and SEM HR (of microsections) analyses showed that both neat and modified CaCO3were well dispersed in PVC matrix and showed very good adhesion to PVC. Comparison of some mechanical properties of both nanocomposites showed slightly worse tensile strength (-2%) and elongation at break (-6%) but much better impact strength (+30%) of PVC/CaCO3- modified with stearin acid.