【摘 要】
：
Several important properties of the micron-powdered Sn-Ag-Cu-Ce solder, including the spreadability, spreading ratio, wetting time, and melting point, were inve
【机 构】
：
College of Materials Science and Technology,14th Research Institute
论文部分内容阅读
Several important properties of the micron-powdered Sn-Ag-Cu-Ce solder, including the spreadability, spreading ratio, wetting time, and melting point, were investigated for verifying the effects of rare earth element Ce on solderabilities of micron-powdered Sn-Ag-Cu solder. The solidus and the liquidus of the micron-powdered Sn-Ag-Cu-Ce solder are 193.6℃ and 218.4℃, respectively, about 28℃ and 3℃ lower than the melting point of the block Sn-Ag-Cu solder, which reminds the existence of the surface effect of the micron-powdered solder. By adding Ce into Sn-Ag-Cu alloy, its wetting time on pure copper can be obviously decreased. For the Sn-Ag-Cu-0.03%Ce, the soldering temperature is 250℃, and the wetting time on pure copper is close to 1s, with the soldering temperature approaching to 260℃, the wetting time is dropped to 0.8s, which is close to the wetting time, 0.68s, of Sn-Pb solder at 235℃.
其他文献
Nanostructured (NS) W-Cu composite powder was prepared by mechanical alloying (MA), and nanostructured bulk of W-Cu contact material was fabricated by hot press
In order to evaluate the degree and severity of Al-Mg-Mn-Sc-Zr alloy in exfoliation corrosion(EXCO) solution quickly and nondestructively, electrochemical imped
The TiB2 dispersion-reinforced copper-matrix composite used as electrode material in resistance spot welding of zinc coated steels was studied. The service life
Layered LiNi1/3Co1/3Mn1/3O2 materials were synthesized using a nickel-cobalt-manganese carbonate precursor obtained by chemical co-precipitation. The [Ni1/3Co1/
YLiF4: Er3 + was synthesized by hydrothermal method. Concentration of Er3 + is changed from 0 to 5 %. The absorption of Er3+ in all samples from 200 to 1200 nm
In the enzymatic membrane reactor for separating casein hydrolysate, backflushing technology has been used to decrease the fouling of the membrane. Predication
This paper deals with channel estimation for orthogonal frequency-division multiplexing (OFDM) systems with transmit diversity. Space time coded OFDM systems, w
This paper proposed a multi-agent based architecture for outdoor mobile robot navigation where event-driven control is used to handle the dynamically changing o
Titanium diboride based composites, good candidates for contact materials, have high hardness, Youngs modulus,high temperature stability, and excellent electric
Selective laser sintering (SLS) is a new process to prepare the polystyrene (PS)/Al2O3 nanocomposites. In this paper, with different laser power and other proce