How the Chemical Milling Titanium process is made?

What is Chemical Milling Titanium?

Chemical milling is a unique chemical machining technique that removing material in a desired shape in a temperature-controlled bath of etching chemicals. A technique in which blind via features, including pockets, channels, etc., are produced by chemically etching materials. It also eliminates material from every surface of the component to save weight. During chemical machining (CM), the material is removed from specific workpiece locations by immersing the workpiece in a chemical reagent or etchant. This etcher can also be acid and alkaline solutions.

When metals corrode or chemically dissolve, the material is removed through microscopic electrochemical cell action. All exposed surfaces are dissolved and etched by this controlled chemistry, although the penetration rate for material removal is very low, perhaps only 0.0025-0.1 mm/min. The etched metal is usually very thin, such as sheet metal or foil. When performed by experienced technician personnel, chemical grinding is a efficient procedure that can save manufacturers time and and make the appearance perfect.

Chemical Milling Process

Most Chemical Milling Titanium aluminide (TiAl) castings for the automotive and aerospace industries, such as turbines, are high-value components with complex geometries. Due to the high reactivity of TiAl cast into ceramic molds, most castings require post-treatment to remove a brittle surface layer called alpha case.

Additionally, the complex geometry and thin walls of such parts make it difficult to cast net-shape parts; therefore, near-net-shape parts are typically produced with machining allowances to improve mold filling. better mobility. To address this technical limitation, this layer and machining allowance was eliminated using a chemical milling process.

Therefore, this experimental work aims to help understand the effect of this finishing process on the surface quality of TiAl castings including roughness, dimensional accuracy and microhardness and intends to determine which of the two chemical solutions tested is more suitable for TiAl Chemical milling of castings.

How Chemical Milling Works

Chemical etchants are the basis of chemical processing operations. Mixtures of strong acids that react with metals are called etchants. When immersed in water, the etchant reacts with the workpiece, dissolving the metal surface from the workpiece at a consistent rate. Apply an elemental coating of a chemical agent "masking agent" to the workpiece before machining to achieve the desired shape or structure.

Applying mask layers on surface of the components that we don’t want to have chemical milling onto, in this way, we can locate the chemical milling area exactly and visible, of course this process needs professional skills. Some factors are very important, including agitation, temperature, processing time, acid concentration, and processing depth of cut or etch are just a few variables to consider when determining how long to leave reagents in place. Finally, once the desired result is achieved, the chemicals are removed from the part and polished to remove the chemical which on the surface.

Chemical Milling Process

Chemical Milling Titanium is a very complicated process that requires professional personnel to operate. If you are a buyer and need to find a factory to do chemical milling, it is best to choose a company with a long business history, a mature processing team and mechanical equipment, and a good reputation service provider, which will save a lot of unnecessary trouble in the follow-up cooperation.

Surface cleaning: Any workpiece must ensure that the surface is free of impurities, corrosion, and foreign matter. Therefore, cleaning is the first step. Cleaning is accomplished using a high-pressure water jet, alcoholic liquid, and diluted HCl. Cleaning is not an easy task and improper cleaning can lead to inaccurate final measurements, poor protective coating adhesion and poor metal solubility. It can also cause the mask to peel off, allowing the etchant to flow behind the mask, and destroying the geometry. After the workpiece is cleaned, it is dried with a hot air blower. Modern CNC machinery can be used to perform cleaning operations.

Masking: Applying a masking agent on the surface of the workpiece is an important step in the process of grinding, and the integrity of the masking must be guaranteed. In the first step, the process is covered with a polymer or rubber coating. Second, the mask prevents the etching process from continuing in areas that do not require processing. The entire workpiece is covered with a mask except for the part to be machined.

Etching: This is the process of removing essential metals. Next, after the specific masking work, the workpiece is immersed in the chemical reagent tank, while the heater and agitator are turned on. Immediately after immersion, the etchant reacts with the uncovered parts of the workpiece. As a result, the workpiece reacts with the high concentration of acid, changing its chemical properties. Due to this reaction, the predetermined portion is melted and separated from the workpiece layer by layer. During this process, the length of the workpiece inclination is exactly the same as the cutting depth. Therefore, the more metal is removed from the workpiece, the longer it remains in the etchant. vice versa.

Asianstar professional CNC machining titanium parts

CNC machined titanium parts are mainly used in the aerospace, automotive, energy industries and are widely used in the medical field due to their biocompatibility. The most common ones are in the automotive and energy industries, and most businesses need this processing, so it is very important to choose a reliable service provider.

Titanium is an easy-cutting material for machining. It is suitable for various CNC processing techniques. Generally, titanium parts are made by titanium cutting, titanium turning, titanium milling, drilling and grinding. Additional surface finishing is uncommon, but Asianstar offers a comprehensive service.

AsianStar is a professional CNC machined parts manufacturer with a team of skilled engineers who are very knowledgeable about CNC titanium machining, specializing in titanium machining and CNC machining of titanium parts. We have lathes, mills, CNC centers and more that have long been used to produce titanium parts. Most titanium parts use material codes like Grade 5 (Ti 6Al-4V), Grade 2, Grade 7, Grade 23 (Ti 6Al-4V Eli). But the equipment provided by AsianStar can meet all the needs of customers.

When choosing a service provider, customers not only have high requirements for processing equipment and technology but also pay great attention to service attitude and price. The AsianStar professional engineer team has experience in 2005. We produce many titanium parts for global customers with our professional knowledge. Customers form partnerships, always choosing the most suitable facility to carry out components at competitive prices.