Firstly, the type of bonding material should be considered when selecting adhesives. Sheet metal materials mainly include steel, aluminum, stainless steel, and other metal materials. Different metal surfaces have different chemical properties and surface treatment methods, which also differ in their adhesion ability to adhesives. For example, epoxy resin-based adhesives have good bonding properties for steel, while polyurethane-based adhesives are more suitable for aluminum. Therefore, it is necessary to clarify the material of the bonded sheet before selection and choose an adhesive with good compatibility.

　　Secondly, the usage environment is crucial for the selection of adhesives. For sheet metal structures that work in high temperature, low temperature, humid, or corrosive environments, higher requirements are put forward for the heat resistance, moisture resistance, and chemical resistance of the adhesives. For example, adhesives used in the engine compartment of cars need to have good high-temperature resistance and anti-aging properties; while for outdoor sheet metal components, the adhesives need to have excellent anti-ultraviolet and anti-mold properties. Therefore, the corresponding type of adhesive should be selected according to the specific application scenario.



Moreover, different sheet metal applications have different requirements for bonding strength, flexibility, and curing time. For structural components that need to withstand greater stress, such as body structures and aviation sheet metal parts, high-strength structural adhesives such as modified epoxy resins or polyurethane structural adhesives should be preferred; while for applications that require certain flexibility and cushioning properties, such as electrical enclosures and decorative panels, elastic silicones or acrylic adhesive resins can be selected. In addition, the curing conditions of the adhesive, such as whether it requires heating curing or the time required for room temperature curing, should also be considered to match the production process.



Finally, it is also necessary to consider factors such as cost, environmental protection, and construction technology. With the increasingly stringent environmental regulations, water-based adhesives and solvent-free adhesives are gradually becoming a trend. In addition, the ease of operation of adhesives, as well as the coating methods (such as dot glue, brush coating, and spraying) will also affect production efficiency and product quality.



In summary, the selection of adhesive in sheet metal bonding should comprehensively consider material compatibility, usage environment, performance requirements, as well as process and environmental factors. Only by making a scientific choice based on a comprehensive evaluation can the connection strength, durability, and reliability of the final product be ensured, thereby enhancing the overall manufacturing level.