Enterprise manufacturing operations are made up of interlocking, overlapping and critically interdependent processes. Each process in this symbiotic web consists of a series of steps that are only successful when the invisible details are unshrouded and subject to quantitative quality parameters.
Processes do not readily reveal the details that they rely on, but if manufacturers adjust their eyes when they peer into the minutiae, the hidden image begins to materialize.
Demystifying manufacturing processes that produce unexplained, intermittent failures requires shining a light on the root causes where they are actually occurring.
When a polymer overmolding only sticks to a metal component 60% of the time; when a protective parylene coating fails to keep circuit boards from exposure to moisture; when ink is inexplicably only able to print on some sections of polypropylene film - in all these scenarios the origins of the failure are not obvious and, often, the results don’t change when the usually suspect variables are tweaked.
To illuminate what process elements are instigating performance-degrading defects, manufacturers need proactive data collection and system optimization. Operational visualization prevents processes from ever producing faulty products because the smallest elements are magnified, measured and managed.
For true process control, objective quality measurement of all process critical elements, all the way down to the literal molecular level, must be implemented from beginning to end. Manufacturing involving any cleaning, bonding, coating, printing, painting or any other adhesion processes, is disastrously vulnerable to seemingly mysterious failures if material surface quality isn’t inspected with the same precision and accuracy as the dimensions of any machined or molded part.
This continuation of our compendium of Critical Control Points in manufacturing processes that need a closer look, turns the spotlight on medical devices, electronics, film and packaging, and renewable energy industries. You can read the first article here.
By almost any metric, medical device manufacturers work with some of the most complex processes borne out of the need to meet intense safety requirements and create products that interact with end users in more intimate ways that no other industry. Medical devices have been utilizing the most advanced materials and processes for years and manufacturers of these products are familiar with the challenges that arise when trying to assemble, bond and coat dissimilar materials, especially with strangely-shaped or very small components.
The life-threatening nature of a medical device that doesn’t operate properly necessitates that every single part that is produced be utterly defect free. Often this is done by undergoing massive work upfront when developing production designs that will yield flawless results 100% of the time. This needed level of perfection is only possible if not only efficiencies are built in from the very beginning, but a system of checks on those efficiencies to make sure they are always meeting throughput and, most importantly, quality standards.
For more information on what steps to take to actually get to the root cause of adhesion and cleanliness issues, download our free eBook: Checklist: Adhesion Failure Root-Cause Analysis for Manufacturers
It’s well known and understood how cleanliness is paramount to safe medical device manufacturing for sanitization; but in order to ensure coating adhesion, strong bonded assemblies of metal components and hundreds of other adhesion-related processes, surface cleanliness needs to be measured and tracked. Cleanliness for the purpose of creating certainty that adhesion will be successful cannot be overlooked.
Here’s a list of common adhesion and cleanliness processes for medical device manufacturers that need to have quantitative quality standards applied and continuously validated through precise, non-destructive and accurate data collection:
A revolutionary prosthetics company knew that their unique and innovative product was changing lives, so there was no tolerance for failures. As the technology surrounding prosthetics continues to grow, companies are building products that are as strong as the human body. The inorganic components must withstand the stresses of weight bearing, pivoting, uneven surfaces and so on, but also must be comfortable and lightweight. This innovative company produces a prosthetic that specifically mimics the human form. Prosthetics are meant to catalyze, not hinder an individual’s physical ability, so the expectations of this product are extremely high and there is no room for error or failures.
This manufacturer needed a way to verify the bonds of their dissimilar materials which included carbon fiber and titanium. Adhesive bonding was necessary as traditional fasteners would not be able to withstand the varying stresses of constant, real-world usage.
In preparation to bond, the manufacturers sanded and solvent wiped the material. Verifying this surface treatment would be the key to a successful and reliable bond. The manufacturer was struggling to find an accurate and precise way to verify this surface preparation on the kind of unusual geometry of the material they formed into shapes that best enacted the motor functionality of human bodies.
Using a simple, fast and production-level surface energy gauge (surface energy is the characteristic of a material that changes during cleaning and treatment and is directly related to adhesion) the manufacturer was able to accurately determine the readiness of their composite and metal parts. Through quantifiable, accurate process controls, the manufacturer is freed to confidently build revolutionizing products that significantly help amputees live their lives comfortably.
Today, the mobility of electronics allows us to broaden the range of when and where we use them. The electronic components of larger assemblies power the products of nearly every other manufacturing industry. From our hyper intelligent watches to the hi-rel, mission critical military and defense applications, electronics are embedded in the fabric of the world more thoroughly than we could imagine. Consequently, these components need to meet stringent manufacturing standards electronics so when they encounter threats such as water, extreme temperatures, shock and contaminants, the bonds and coatings that make up and protect the circuitry of our lives need to be flawless.
Here’s a list of common places and processes in electronics manufacturing that need to be controlled systematically to ensure zero defect production and also allow manufacturers to shift focus from rework and warranty claims to innovation and progress:
A manufacturer needed a way to ensure the protection of their circuit boards. As the core of any electronic assembly, circuit boards are highly sensitive to threats that cause damage and failure such as moisture, extreme temperature and contaminants. To address this issue, manufacturers apply conformal coating to the circuit board for protection. By conforming to the typography of the circuit board, this coating protects the piece from these environmental threats.
If the surface of the board and components are not chemically compatible with the parylene coating deposited over the assembly then there will likely be delaminations (where the coating pulls away from the board), orange peel defects (where the coating becomes textured and inconsistent), and other failures of the coating to protect the board. When the conformal coating fails then it can lead to dendritic growth on the board and other corrosions that inevitably result in shorts and board failures.
This manufacturer encountered challenges in creating a successful bond between the conformal coating and the circuit boards. BTG Labs was able to guide them through setting up a plasma treatment system that would activate the surfaces of their boards immediately before coating. A board that appears to be clean is likely not ready to be bonded to. The chemical composition of the top few molecular layers must be controlled with precision and an understanding of what substances must be present, what is immaterial to adhesion and what is detrimental to it. Plasma treatment is a powerful way to create a surface that is ready for bonding. To get the most out of these treatments, measurements of the surface quality before and after treatment is vital.
BTG Labs’ biggest contribution to this manufacturer was providing them ongoing data-collection through an in-line automated inspection system that instantly verified that the plasma treatment worked every time. There was no longer any doubt that the coatings would stick uniformly and the electronic devices would be guaranteed to succeed. Scrap was dramatically reduced and output was dramatically increased.
Adhering on film and flexible packaging—whether it’s coating, lamination, metallization, print—can be challenging as the materials generally have very low surface energy, which is difficult to adhere to. So, manufacturers must increase the surface energy through treatments such as corona and flame treatment.
Monitoring these processes can be frustrating at best with traditional techniques like dyne inks, since they are inconsistent, subjective and will only catch a small fraction of defects - an unacceptable track record. Ensuring a fully optimized and validated surface preparation process is crucial for successful adhesion to polymer films.
Here’s a list of common needs in the film and flexible packaging industry:
A world leader in flexible film packaging was frustrated with their inconsistencies in their surface treatment processes and desired a fast, easy, quantitative, and objective method to accurately measure their surface quality across the entirety of their film web.
They had been utilizing dyne inks to measure corona treatment on films. However, they found dyne inks were simply not detecting the contaminant they absolutely knew was present on the film because when they went to print on the treated polymer it would intermittently fail without any discernible pattern. They needed a solution that definitively got to the root cause of the failures and made it possible to permanently fix the problem.
Through rigorous analysis from the BTG Labs’ surface lab we were able to determine that there was migration of a slip residue that made it possible for the film to easily slide over rollers that propelled the sheets through the machinery where the processing was done. This slip was supposed to be isolated to just one side of the film but was making its way to the portions that were to be printed on.
This is a problem that is fairly easily solved through dialing in the parameters of the corona treatment to neutralize this contaminant but without a way of detecting it’s presence, the manufacturer had no clue when the treatment was satisfactorily getting the job done. BTG Labs was able to overhaul their inspection process so that it relied on accurate, predictive data as opposed to subjective ink meanderings.
As humanity’s energy needs grow, the expansion of energy collection and extraction methods is also required. The renewable energy industry is at the forefront of using materials in innovative ways to create machinery that enables us to utilize sources of energy all around us.
From massive composite windmill turbines to hydroelectric power generators, and even using the most advanced technology to build oil pipelines that never spill their contents, the energy industry relies on strong adhesive bonding and flawless manufacturing.
Here’s a list of common applications of adhesion technology in the energy sector that need to be controlled so that our mechanisms of gathering and distributing energy are free from failures due to adhesion breakdowns:
A few years ago, Elon Musk announced the availability of Tesla’s new solar roof. These solar roofs are made to be as low profile and tasteful as any modern shingles; their attractive panels offer roofs from sleek modern to French slate. The solar panels are hidden in a pane of glass which contains a hydrographic coloring--a process that uses water to apply printed designs-- to provide texture and the look of more traditional shingles.
But, these shingles must not only look good, like all solar panels, they must be tough enough to withstand elemental threats.
Wind, rain, snow, sun, extreme temperatures--these are all stresses to any outdoor structure, especially solar panels that are designed to be as exposed as possible. Because solar panels serve as an energy source, there is no room for failure in the field. The bonds between the dissimilar materials that make up the panels, along with coatings, laminates and seals, must withstand the rigors of constant environmental bombardment.
BTG Labs has helped manufacturers of solar panels at several steps in their production process to produce a strong, reliable product. The first step is assessing the initial surface cleanliness of incoming materials by applying a quantitative specification that vendors must comply with. The next steps are a series of treatment, cleaning and surface preparation methods before the final assembly. In the case of the Tesla panels, the glass that covers the solar cells are flame treated prior to printing to ensure that the ink would adhere strongly for years without being susceptible to heavy rains or strong winds.
For more information on what steps to take to actually get to the root cause of adhesion and cleanliness issues, read our guide to reexamining your process holistically. The “Checklist: Adhesion Failure Root-Cause Analysis for Manufacturers” eBook is a step-by-step handbook for eradicating adhesion failure from the ground up.