Newsletter Mission Statement Keeping pace with the development of new technologies has always been one of VAC AERO’s main concerns. Given our role as a leader in vacuum heat treating and special processing, the aim of our Newsletter is (1) to facilitate discussion among our customers, technical and educational communities and suppliers on a variety […]
Most base metals typically brazed in vacuum furnaces have a natural oxide “coating” that can inhibit the flow of brazing filler metals.
Conversely, alloys containing appreciable amounts of reactive elements such as aluminum and titanium tend to form oxides at high temperatures which impede the flow of the brazing filler metal. Many of the nickel-base superalloys fall into this category and the severity of the problem varies depending on alloy composition. These materials should be brazed at high vacuum levels of 2 x 10-4 torr or better. There are several reliable techniques for improving the brazeability of difficult to braze materials. These include brush nickel plating of the joint surfaces, chemical etching techniques to remove aluminum and titanium from a shallow layer at the joint surface and using special aggressive braze filler metals with self-fluxing characteristics. The oxides of the less reactive metals like iron, nickel, and cobalt tend to dissociate (break down) under low pressure and high temperature. Therefore, alloys such as the 300 and 400 series stainless steels, carbon steels and many tool steels can be successfully brazed in vacuum at relatively high pressures (1 to 50 microns).
No matter what field you study, an accurate knowledge of its vocabulary is essential to understanding the subject. In the field of vacuum heat treatment, considerable emphasis is placed on the proper use, meaning, and interpretation of certain words or phrases. A brief summary of the terminology including common processes being run is presented below.
Come Visit us at Furnaces North America – Booth 337, Indianapolis, IN – October 8-10, 2018
We’re excited to be exhibiting at the Furnaces North America Conference & Expo in Indianapolis, IN – October 8-10, 2018. If you plan on attending the show, please be sure to stop by our booth number 337 to learn more about our latest vacuum furnaces, and most importantly… we’re interested in learning about you, your business, and your needs. Our sales reps will be available to answer questions about how VAC AERO can help your business with exactly the vacuum processing solutions that you’re looking for! See you there!
Furnaces North America is one of the largest Expos for manufacturers, commercial and captive heat treaters looking for the latest in technology, trends, and training that can energize their productivity and profits. The FNA creates an exciting mix of education, technology, networking and exposition opportunities. Join the innovators and decision makers in the heat treating industry from around the world. You can’t afford to miss the FNA Conference and Expo!
For more information please visit: Furnaces North America
Maintenance procedures and safe working conditions are essential in maintaining vacuum furnaces as is proper preparation of components to be heat treated prior to charging to the furnace.
VAC AERO International operates more than a dozen vacuum furnaces in its own heat treating facilities. In addition, it has manufactured hundreds of vacuum furnaces for sale to the global market. Through these activities, the company has gained extensive experience in the care and maintenance of vacuum furnace equipment.
Applications involving vacuum heat-treating are typically performed for one of the following reasons:
- Processes that can be done in no other way than in vacuum;
- Processes that can be done better in vacuum from a metallurgical standpoint;
- Processes that can be done better in vacuum from an economic viewpoint;
- Processes that can be done better in vacuum from a surface finish perspective.
All of the common (and several uncommon) heat treatment processes can be run in vacuum, from annealing and brazing to sintering and tempering. Many companies that currently outsource vacuum heat-treating ask themselves if they would be better served by setting up this capability in-house. Others who already have an in-house heat treat department wonder if switching to vacuum processing will offer them a competitive edge. This article will help address these questions.
Vacuum furnaces are typically characterized by their method of loading, horizontal or vertical, as well as if there is internal load movement, being classified as either batch or continuous (i.e. multi-chamber) types (Fig. 1 – 2). The various furnaces sizes, production capabilities, and feature configurations are almost endless and detailed extensively elsewhere , . Since most vacuum furnaces have a life expectancy of 40 – 50 years, decisions as to what to purchase, and from whom, become very important.
VAC AERO welcomes and encourages applications from people with disabilities. Accommodations are available on request for candidates taking part in all aspects of the selection process. JOB OPENINGS No job openings available at this time.