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Reflow soldering is widely used to manufacture a wide range of electrical components. The tabletop reflow oven forms an integral part of the soldering process, and are also great for DIY component makers. The bench top design of it calls for minimal installation and simple operation for the home or commercial user.
Reflow soldering is commonly used to attach surface mounted components to a circuit board. Less commonly, reflowing can also be used to attach through-hole components to the circuit boards. Solder paste (solder mixed with flux) is used to temporarily attach electrical components to a contact pad. This newly assembled contact pad and attached electrical components are then subject to heating in order to melt the solder, creating a permanent joint. This second step is where the use of this machine comes in.
Reflow ovens must be used so that the areas other than the paste aren't burnt or heated to the point of damage. The four specific features of the oven successfully targets the paste. These consist of preheat, soak, reflow, and cooling stages.
The oven begins at the preheat zone, which is often the lengthiest of the stages. During this stage, the temperature increases at a rate of between 1 and 3 degrees Celsius per second. This temperature change is referred to as the ramp-up rate. The controlled ramp-up rate is essential in avoiding thermal shock or cracking of the components.
The couple minutes after the preheat stage is the thermal soak zone. The oven exposes the combined component to a brief period where the paste is secured and the fluxes are stimulated. There's a restricted range of temperature that is released in order to prevent potential splatter or oxidization. This range not only applies to the maximum heat, but also the minimum limit since the fluxes still need a certain amount of heat to activate.
The re-flow zone, or "time above liquidus" (TAL), is the peak temperature stage. This is usually a temperature 20 to 40 degrees Celsius above liquidus. The appropriate temperature is determined by the component that has the lowest heat tolerance.
As a general rule, this temperature will be below 200 and 60 degrees Celsius, as this is the temperature at which damage may occur to the internal makeup of the components. The TAL is as important as selecting the correct temperature because only the correct time above reflow will allow the individual solder powders to combine and form the required bond. Incorrect TAL can result in either drying of the paste or create defective joints.
The re-flow oven finishes the entire molding process in its cooling stage. The melted paste between the components need to cool gradually to create a cohesive unit. If the component isn't cooled with proper measures, the unit might produce intermetallic accumulation or even go into thermal shock. Proper cooling actually requires a faster temperature change rate than heating for it to achieve the best durability. This faster cooling rate usually lies around 4 degrees Celsius per second.
Reflow soldering is commonly used to attach surface mounted components to a circuit board. Less commonly, reflowing can also be used to attach through-hole components to the circuit boards. Solder paste (solder mixed with flux) is used to temporarily attach electrical components to a contact pad. This newly assembled contact pad and attached electrical components are then subject to heating in order to melt the solder, creating a permanent joint. This second step is where the use of this machine comes in.
Reflow ovens must be used so that the areas other than the paste aren't burnt or heated to the point of damage. The four specific features of the oven successfully targets the paste. These consist of preheat, soak, reflow, and cooling stages.
The oven begins at the preheat zone, which is often the lengthiest of the stages. During this stage, the temperature increases at a rate of between 1 and 3 degrees Celsius per second. This temperature change is referred to as the ramp-up rate. The controlled ramp-up rate is essential in avoiding thermal shock or cracking of the components.
The couple minutes after the preheat stage is the thermal soak zone. The oven exposes the combined component to a brief period where the paste is secured and the fluxes are stimulated. There's a restricted range of temperature that is released in order to prevent potential splatter or oxidization. This range not only applies to the maximum heat, but also the minimum limit since the fluxes still need a certain amount of heat to activate.
The re-flow zone, or "time above liquidus" (TAL), is the peak temperature stage. This is usually a temperature 20 to 40 degrees Celsius above liquidus. The appropriate temperature is determined by the component that has the lowest heat tolerance.
As a general rule, this temperature will be below 200 and 60 degrees Celsius, as this is the temperature at which damage may occur to the internal makeup of the components. The TAL is as important as selecting the correct temperature because only the correct time above reflow will allow the individual solder powders to combine and form the required bond. Incorrect TAL can result in either drying of the paste or create defective joints.
The re-flow oven finishes the entire molding process in its cooling stage. The melted paste between the components need to cool gradually to create a cohesive unit. If the component isn't cooled with proper measures, the unit might produce intermetallic accumulation or even go into thermal shock. Proper cooling actually requires a faster temperature change rate than heating for it to achieve the best durability. This faster cooling rate usually lies around 4 degrees Celsius per second.
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