Aluminum oxide is a general purpose loose grain abrasive used in a variety of blasting, polishing, lapping, or other finishing applications. It is also referred to as Brown Fused Aluminum Oxide, or Brown Aluminum Oxide.
Abrasive Products has an abrasive recycling for many of the products we offer. Brown Fused Aluminum Oxide is one abrasive that can be recycled. The spent media must meet certain criteria for a recycling program. Sufficient volume of product recycled is required and the media must be free of hazardous materials.
The grinding operation gives workpieces their final finish, minimizing surface roughness through the interaction between the abrasive grains of a tool (grinding wheel) and the workpiece. However, excessive grinding wheel wear due to friction renders the tool unsuitable for further use, thus requiring the dressing operation to remove and/or sharpen the cutting edgesof the worn grains to render themreusable. The purpose of this study was to monitor the dressing operation using the acoustic emission (AE) signal and statistics derived from this signal, classifying the grinding wheel as sharp or dull by means of artificial neural networks. An aluminum oxide wheel installed on a surface grinding machine, a signal acquisition system, and a single-point dresser were used in the experiments. Tests were performed varying overlap ratios and dressing depths. The root mean square values and two additional statistics were calculated based on the raw AE data. A multilayer perceptron neural network was used with the LevenbergMarquardt learning algorithm, whose inputs were the aforementioned statistics. The results indicate that this method was successful in classifying the conditions of the grinding wheel in the dressing process, identifying the tool as sharp (with cutting capacity) or dull (with loss of cutting capacity), thus reducing the time and cost of the operation and minimizing excessive removal of abrasive material from the grinding wheel.
Bianchi EC, Aguiar PR, Poggi MR, Salgado MH, Freitas CA, Bianchi ARR (2003) Estudo do Desgaste Abrasivo das Resinas Compostas Disponveis no Mercado Brasileiro (Study on abrasive wear of composite resins in the Brazilian market). Mater Res 6(2):255264
Pontes FJ, Paiva AP, Balestrassi PP, Ferreira JR, Silva MB (2012) Optimization of radial basis function neural network employed for prediction of surface roughness in hard turning process using Taguchis orthogonal arrays. Expert Syst Appl 39:77767787
Moia, D.F.G., Thomazella, I.H., Aguiar, P.R. et al. Tool condition monitoring of aluminum oxide grinding wheel in dressing operation using acoustic emission and neural networks. J Braz. Soc. Mech. Sci. Eng. 37, 627640 (2015). https://doi.org/10.1007/s40430-014-0191-6
Manufacturers and industrialists know that when youre working with aluminum on a regular basis, its imperative that you have at your disposal a number of machining techniques to work your metal to the exact shape and design that you want. This applies whether you will be working the material in house or contracting out the job to a third party. For instance, when you need to grind aluminum sheet or plate for an application, having a variety of grinding machines and blades at your disposal is essential.
This is because aluminum, despite its popularity and versatility compared with most other metals, is one of the most difficult materials to grind. If you dont know what you are doing, grinding aluminum can cause major problems. Luckily, Clinton Aluminum is here to help.
Grinding is a cutting method that involves the use of a grinding wheel to abrasively machine the material that you wish to cut. In manufacturing and tool making there are a wide variety of grinding machines and methods that can be used on many different materials, including metals such as aluminum and stainless steel.
Grinding is recognized for producing very fine finishes and accurate shapes, while also having the ability to rapidly cut large volumes of metal in mass production contexts. In general, it is better suited for cutting very hard materials than other forms of machining and traditionally was one of the only practical methods of cutting materials such as hardened steels. One reason it is commonly used with plate and sheet is its ability to make very shallow cuts, for instance reducing a shafts diameter by half a thousandth of an inch.
While it might not seem like it when first encountered, grinding is a true metal-cutting process. The way it works, at the microscopic level, is that each grain of the abrasive material serves as an individual cutting edge. As the grinder is applied to the material to be cut, the abrasive shears tiny chips. However, grinding is often thought of as a separate category from cutting and is referred to as such on shop floors.
In order to accommodate the wide variety of materials that need to be ground, a host of machines and methods have been developed over the years, each designed to handle a particular type of job. The machines themselves can range in size from handheld power tools such as angle grinders and die grinders to expensive industrial machines and bench grinders.
One of the most common methods is known as surface grinding, which uses a rotating abrasive wheel to remove material and create a flat surface. Typical tolerances that are achievable with surface grinding tools are 2104 inches on a flat material and 3104 inches on a parallel surface. A surface grinder is made up of an abrasive wheel, a work-holding device (referred to as a chuck), and a reciprocating table.
Cylindrical grinding is used, as the name suggests, to grind cylindrical surfaces, such as on poles and shafts. The piece that is being ground is mounted onto the machine and rotated by a device known as a center driver. With most machines, its possible to rotate the abrasive wheel and the workpiece separately and at different speeds. In general, there are five types of cylindrical grinding, known as outside diameter grinding, inside diameter grinding, plunge grinding, creep feed grinding, and centerless grinding.
Creep-feed grinding is a relatively recent development in grinding, having been developed in the late 1950s. This is a method for removing material at high rates of speed at depths of up to 0.25 inches. It can be nearly twice as fast as a precision grinding method. This method does have certain disadvantages, such as a constantly degrading wheel, a need for high spindle power, and a limited machining area. New advances have allowed for constant wheel sharpness and even faster grind times.
Other forms of grinding include high-efficiency deep grinding, peel grinding, ultra-high speed grinding, form grinding, internal grinding, pre-grinding, electrochemical grinding, and electrolytic in-process dressing grinding.
Aluminum poses specific problems that must be taken into consideration when grinding aluminum alloys. This is because aluminum is relatively soft and it melts easily. If you dont know what you are doing, its easy for the aluminum to start melting as you grind it, coating the wheel.
As the grinding stone gets covered in small bits of aluminum, the grit of the stone is no longer exposed. The aluminum that gets caught in the wheel rubs against the aluminum being cut, increasing the heat even further and melting the metal even faster. An inexperienced grinder will push the piece against the wheel more forcefully, leading to increased friction. In the worst cases, the wheel will heat up to the point that an explosion will occur.
In order to avoid such scenarios, its important to use a grinder that can be dressed during the grinding process. Dressing is a technique of knocking loose the excess material from the grinding wheel, alternatively known as sharpening the wheel. If you dont have a machine that can be dressed in process, then you would have to start and stop the grinding very frequently and dress the wheel by hand.
Grinding aluminum sheet and plate is a delicate operation and requires a certain level of expertise. Understanding the specific properties of the alloy or grade of aluminum you are working with is essential to ensure a smooth grinding process. Clinton Aluminum always has a wide variety of sheet and plate in stock in the most popular alloys.
We are committed to being more than just a materials supplier, however. Our team of experienced and dedicated technical professionals work with our customers through every step of production, from picking out the right material to using the right machining tools, to perfecting the prototyping process before going to market.
Pressure and heat are the main culprits of frustration when working with aluminum. To improve the quality, safety and productivity of your work while reducing downtime and labor costs, here are some insights on how to choose the right wheel or disc to address the needs of the pre-weld and post-weld operation.
While aluminum has been used in shipbuilding for decades, a growing number of other applications now use aluminum in metal fabrication due to its high strength-to-weight ratio and superior corrosion resistance. Since 2005, the demand for the material has grown at a faster rate than any other metal or alloy primarily because of its increased popularity in additional market segments, such as structural framing, trailer manufacturing and repair, service decks and ladders, and platform construction. Perhaps most notably, Ford switched to aluminum as the body material their most popular truck, the F150.
For all of the benefits that aluminum offers fabricators, it can also bring challenges: it can be one of the more difficult materials to cut, grind and finish efficiently because it has a lower melting point than other metals. The heat and friction that build up during these processes quickly melts the aluminum, causing it to stick and accumulate on the abrasive to the point that its taller than the cutting grain. This loading or clogging of material eventually prevents the abrasive from cutting and causes the wheel to stop working altogether. In addition to loading, other common challenges when working with aluminum include contamination and the potential for porosity and oxide inclusions, and achieving the desired finish:
Many welding professionals today approach aluminum cutting, grinding and finishing by relying on one or more of the following tools or methods. Each of these, however, also have disadvantages in terms of cost, quality, productivity and safety:
A BETTER CHOICE FOR CUTTING, GRINDING AND FINISHING ALUMINUM The goal when choosing a product for cutting, grinding and finishing aluminum is to have the right wheel or disc to address the needs of the pre-weld and post-weld operation. The right choice can help shops gain better quality, safety and productivity. It can also minimize downtime and labor costs. A type 27 grinding wheel that doesnt load is an option when cutting and/or grinding aluminum. These wheels feature grain blends selected for consistent performance and a contaminant-free bond. High quality, aluminum-specific products are designed to cut smoothly while minimizing burr formation. They also significantly reduce the noise and vibration through the cut, and are therefore easier to control. Wheels are available for cutting or grinding only, or as combination cutting/grinding wheels.
Resin fiber discs (RFDs) designated for aluminum are a good option for grinding, blending and finishing. RFDs are used with a firm rubber backing pad that offers flat, consistent contact with the material during use, making them easier to control and blend. The best discs are pre-treated or coated with a lubricant to reduce heat buildup while grinding. This feature helps delay melting of the aluminum, preventing the disc from loading and offering higher cut rates, along with a longer product life. Another alternative to a resin fiber disc for grinding, blending and finishing are treated or top-coated flap discs. These discs are available in a variety of grain options; however, they are not as popular in the industry since they are more pliable and require a higher skill set to gain the desired surface finish. That said, they offer the advantage of time savings in some cases, since they allow for grinding and finishing in one step; there is no need to switch from a Type 27 grinding wheel to a resin fiber disc to complete the job.
Since aluminum is easy to damage, some welding operators use non-woven hand pads or 0000 steel wool to finish by hand and minimize potential damage to the part. Non-woven discs and wheels, though, can save time compared to manual finishing. Non-woven discs and wheels are ideal for decorative finishing, satin and antique finishes, final sanding, soft metal finishing and fine burr removal. Power brushes for cleaning also help get the job done quickly without applying excessive pressure that could damage the aluminum.
FINAL THOUGHTS Pressure and heat are the main culprits of frustration when working with aluminum. It is important to use high quality, contaminate-free products and to let the wheel do the work. Applying pressure to increase performance will only lead to additional frustration and compromise quality. Also, a strong, consistent weld begins with proper surface preparation. The cleaner the seam being welded, the better the weld penetration. For best results always use a product that is designed for use on aluminum. The best products will cut cleanly and smoothly without pitting, gouging or undercutting. There are several high performance products available to get the job done quickly and efficiently, so always consult your trusted distributor abrasive manufacturer to understand what options are available for the application. For more information and to view an aluminum solutions guide, please click here.
Its interesting to note how you explained that since aluminum is easy to damage, some welding operators use non-woven hand pads or 0000 steel wool to finish by hand and minimize potential damage to the part. You bring up a good point here, one Im sure those interested in the finishing of aluminium will be glad to have been made aware of. My interest in this came around after having a conversation with my brother on industrial aluminum polishing last Tuesday afternoon. I wanted to do know more about and thus, my research led me here. Thanks for all the information! https://budspolishing.com/services/industrial-aluminum-polishing/
Together with Sunrise, Trilogy Machinery Inc. (Belcamp, MD), the exclusive U.S. distributor for Sunrise ironworkers, has increased the standard warranty for Sunrises ironworkers and punching machines to three years for parts and one year for labor.
Welding automation company Pemamek Oy (Loimaa, Finland) and its North American subsidiary, Pemamek LLC (Liberty Township, OH), have named Kevin R. Antoniak to the position of Midwest regional sales manager.