Flexible PCB Manufacturers Test For Thermal Reliability
Whether you’re designing for consumer applications or mission-critical projects, your PCB needs to be able to cope with a wide range of environmental conditions. These include exposing your board to high temperatures and varying those temperatures rapidly, which can stress both the circuitry and its physical components. PCB manufacturers ensure the reliability of their products by testing and inspecting them during production. This article will explore how they test rigid-flex PCB prototypes for thermal reliability, as well as the various tests used to evaluate their durability and performance.
During a thermal shock test, your product’s circuit board is exposed to rapid temperature changes over long periods of time. The test is designed to replicate the conditions that might be experienced in a deployed environment. The most common methods for assessing thermal shock resistance are using IST or MT/MT, where coupons are heated and stressed over a period of time. The test continues until a pre-determined rejection criterion is met, such as a maximum number of cycles or a specified percentage increase in each of the interconnects’ circuits’ elevated resistance.
The sensitivity of a flex PCB’s interconnects to temperature changes depends on the materials used in its construction. Some components, such as passive elements and metallized dielectrics, may fail immediately when exposed to extreme temperatures. Other parts, such as conductive metals and solder joints, may become fatigued and prone to failure under sustained mechanical stress. In addition to thermal stresses, your PCB might need to withstand vibration and shock tests to evaluate its ability to withstand physical stress.
How Flexible PCB Manufacturers Test For Thermal Reliability
A key component of any flexible pcb manufacturer is its adhesive, which needs to withstand the strains and stresses of assembly and field installation. To make sure your adhesive is up to the task, your PCB manufacturer will use a series of tests. For example, a typical tensile test is performed by placing your product’s PCB in a chamber and applying constant pressure for 10 minutes. The test is then inspected for signs of damage, which could indicate that your adhesive is weak or compromised in some way.
Other tests used to evaluate a flex PCB’s strength and durability include cyclic humidity and mechanical shock testing. These tests are often performed on the same samples used in a tensile test. For example, your PCB will be weighed before and after being placed in a humid environment to measure its weight change. A significant weight change indicates that the board is not sufficiently resilient to the environment in which it will operate.
These are just a few of the tests your PCB prototype will undergo to meet your project’s specific requirements and standards. As you can see, the process is quite involved, but it’s crucial that your flex or rigid-flex PCB prototype is able to withstand the rigours of rigorous testing. If your PCB isn’t robust enough, it will be subject to premature failure within the field and possibly affect its operating performance and safety.
