SMT Solder Paste Manufacturers.
Focused on SMT soldering processes, a one-stop electronic soldering solutions provider.
Here you can find knowledge about Soldering Auxiliary Materials, including but not limited to usage methods, installation techniques, troubleshooting and more. Focused on SMT soldering processes. If you can't find what you need, please contact us anytime.
Improper storage of solder paste will lead to reduced activity of SMT solder paste, segregation of metal content, and imbalance in solvent volatilization. Continuing to use it for soldering on the production line can easily cause defects such as cold solder joints, tombstoning, solder balls, and bridging, and in severe cases, lead to functional failure of the entire batch of PCBA. Based on 20 years of practical experience in SMT production lines, this article directly addresses the typical risk points of the disconnect between solder paste storage and usage.
Published: 2026-08-27
The whitening of wave soldering joints is mostly caused by insufficient purity of solder bars. GB/T 8012—2013 stipulates that the Sn content in tin-based solder shall not be less than 99.3%, the upper limit of Pb impurity is 0.005%, and the total content of harmful elements such as As, Sb, and Bi shall not exceed 0.01%. In actual production lines, every 0.1% decrease in solder bar purity may increase the thickness of the solder joint oxide film by 12%, leading to an abnormal increase in reflectivity and a grayish-white appearance.
Published: 2026-08-27
An excessively large ramp-up slope during reflow soldering can easily cause typical solder paste defects such as solder paste splashing, solder balls, tombstoning, and poor wetting. The root causes are violent vaporization of the flux, accelerated oxidation of solder powder, and unbalanced thermal stress on components. Production lines should address this by stepwise optimizing the preheat zone slope, calibrating thermocouple positions, shortening the soaking time, and strengthening cold storage management for solder paste.
Published: 2026-08-27
Oxidation of PCB solder pads severely impairs the wettability of SMT soldering and the formation of intermetallic compounds. Even using high-activity solder paste and optimizing the reflow profile cannot compensate for the lack of interfacial bonding strength. The solderability of copper pad surfaces must be restored through source control, chemical activation, and coordinated process parameters.
Published: 2026-08-27
In nitrogen soldering, the dew point control of solder paste directly determines the wettability and void ratio of solder joints. Practical measurement experience shows that the dew point needs to be stably maintained between -40℃ and -50℃. A dew point below -55℃ can easily make the oxide film of the solder paste difficult to break, while a dew point above -35℃ will cause a significant decrease in the activity of the flux. It is only truly effective when paired with a nitrogen purity of ≥99.995% and an oxygen content of <50ppm.
Published: 2026-08-27
Rapid oxidation of wave soldering bars will significantly shorten the service life of solder pots and increase solder joint defect rates. Controlling the molten solder temperature is the core means of suppressing solder bar oxidation. In actual production, the wave soldering machine temperature should be stably maintained within the range of 250℃±2℃. Combined with nitrogen protection, regular dross removal, and monitoring of solder bath level, the oxidation rate of wave soldering bars can be effectively delayed.
Published: 2026-08-27
SMT solder spike problems mostly stem from improper matching of temperature and materials during solder wire welding. Based on measured production line data, this article explains in detail the setting logic for a preheating zone of 120℃～150℃, a soaking zone of 160℃～180℃, and a reflow peak of 235℃～245℃. Combined with parameters such as a solder wire diameter of 0.3mm～0.5mm, RMA grade in J-STD-004B for flux activity, and a chain speed of 1.2m/min, it provides directly applicable temperature zone fine-tuning solutions and root cause determination paths for solder spikes.
Published: 2026-08-27
Poor soldering performance on manual solder wires is mostly caused by the imbalance between flux activity and residue. When selecting a flux, focus on four hard parameters: rosin-based proportion, halogen content, activation temperature, and spreadability. A chloride ion content of 0.5%~1.2%, an activation range of 180℃~220℃, and a spreadability of over 92% are the key thresholds for a reliable manual solder wire flux.
Published: 2026-08-27
The BGA cold solder joint issue cannot be simply attributed to SMT solder paste; a systematic investigation is required into hard parameters such as reflow profile peak temperature (235±2℃), heating rate (1.2~1.8℃/s), soak time (60~90s), as well as solder paste metal content (88.5~89.2%), viscosity (750~850 Pa·s), and particle size D50 (20~25μm). Switching solder paste is only effective when verification confirms insufficient flux activity or excessive metal powder oxidation.
Published: 2026-08-27
The selection of SMT soldering materials must match the specific process path. The activity, melting point, metal content, particle size distribution, and flux type of solder paste, solder wire, solder filament, and solder bar directly affect printing accuracy, reflow forming, and the reliability of manual repair soldering. For example, lead-free solder paste commonly uses the Sn96.5Ag3.0Cu0.5 composition, has a particle size D50 of 25±5μm, and its viscosity is controlled at 700±150Pa·s, while solder wire for manual soldering needs to match the soldering iron temperature of 320℃～350℃ and the heat capacity characteristics of the pads.
Published: 2026-08-27Our technical team is always ready to provide professional solder material selection advice and SMT process solutions.