Here, in a certain high density interconnect (HDI) printed circuit board, the effect of copper sulfate and sulfuric acid on the filling effect of a blind hole with a certain diameter and depth was investigated by making a blind hole using a CO₂ laser drilling machine, filling the blind hole via electroplating by simulating the electroplating line in a Halin cell, and observing the cross-section of a micro blind hole after polishing using metallographic microscope, as well as the effect of hole filling, are evaluated. The results show that, under the conditions of a certain plating solution formula and electroplating parameters (current density and electroplating time), the sag degree decreases with the increase in the copper sulfate concentration. When the concentration of copper sulfate increases from 210 g/L to 225 g/L, the filling effect is good and the sag degree is about 0. However, with the increase in sulfuric acid concentration, the sag increases gradually. When the sulfuric acid concentration is 25–35 g/L, both the sag and copper coating thickness are in a small range. Under appropriate electroplating conditions, a better blind hole filling effect can be obtained. The volume of blind hole has a certain effect on the diffusion and exchange of copper sulfate and sulfuric acid, as well as on the concentration distribution of additives.

A larger x _p of M in MB _x causes a lower peak temperature but almost doesn't affect the initial temperature during the dehydrogenation of LiBH ₄ .

Zr_55.7Cu_22.4Ni_7.2Al_14.7 alloy bars were prepared by copper mold suction casting, and the structure and thermodynamic properties of the prepared specimens were characterized by X-ray diffractometer and differential scanning calorimeter. Furthermore, isothermal crystallization mechanism and crystallization activation energy were investigated by Johnson–Mehl–Avrami model and Arrhenius equation. The results show that the structure of the specimen is amorphous. The glass transition temperature (T_g), onset crystallization temperature (T_x) and crystallization peak temperature (T_p) are 713 K, 779 K, and 781 K, respectively, and supercooled liquid region ( $$\Delta T\, = \,T_{x} - T_{g}$$Δ T = T x - T g ) is 66 K. The crystallization incubation times are shortened and the crystallization transformation rates increase with temperature rising. As the crystallization volume fraction increases, the crystallization nucleation rate shows a trend of first increasing and subsequently decreasing, while the activation energy decreases monotonously, in the same time, the crystallization behavior transforms from interface-controlled to diffusion-controlled growth. The thermal stability of amorphous alloy is also discussed.

In order to improve the friction and wear performance and surface hardness of AISI 1045 steel and expand its application range, this paper carried out the research on friction and wear performance and surface hardness of Zr₆₅Al_7.5Ni₁₀Cu_17.5 crystalline powder (CP) and amorphous powder (AP) after laser cladding on AISI 1045 steel surface. The results show that both CP and amorphous powder (AP) formed a cladding layer on the surface of AISI 1045 steel under laser irradiation. The thickness of the cladding layer is about 400 μm, and the thickness of the AP cladding layer is slightly larger than that of the CP cladding layer. The results show that there are many holes in the AP cladding layer, and holes can be observed at the junction with the matrix; while the CP cladding layer is well combined with the matrix and no holes are observed. The friction performance of CP cladding layer is better than that of AP cladding layer. In the wear marks of the AP cladding layer, there are bonding areas, while the wear marks of the CP cladding layer have a furrow-like morphology, and part of the matrix is exposed. The surface microhardness and average microhardness of AP cladding layer are 49% and 94% higher than that of CP cladding layer, respectively. Hardness modification has obvious advantages. The reasons for porosity, large friction coefficient and low stability of the friction experiment of the AP cladding layer are analyzed and discussed. The ideas and methods for improving the laser irradiation to achieve both high wear resistance and high strength of the AP cladding layer are proposed.