Vacuum Heat Treating: Education & Training
Update on Vacuum Furnace Gauges
A vacuum Gauge is a pressure measuring instrument that measures pressure in a vacuum (i.e., in a vessel operating at sub-atmospheric pressure). Depending on the type of vacuum system (Fig. 1) and the required operating vacuum level, different vacuum gauges[...]
Instrumentation and Process Control in Vacuum Furnaces
The type and reliability of instrumentation and process controls used on vacuum furnaces in the heat treatment industry (Fig. 1) is critical to both the performance of the vacuum furnace itself as well as the results that are achieved when[...]
Process Applications Run in Vacuum Furnaces – Part Two
The advantages of processing in vacuum including some of the materials and common processes have already been discussed (Process Applications Run in Vacuum Furnaces – Part One). Here we look at custom heat treatment processes conducted in vacuum furnaces including vacuum[...]
Process Applications Run in Vacuum Furnaces – Part One
There is a constant need throughout the industry to produce the highest quality parts to the most stringent product specifications. Both long-established and new materials are being employed to meet the needs of lighter, stronger, smaller and more efficient designs,[...]
Vacuum Technology with The Heat Treat Doctor
Discolored Work in a Vacuum Furnace – The Heat Treat Community Answers the Clarion Call
For those of us who participate in the Heat Treatment group of LinkedIn (https://www.linkedin.com/groups/1855932), which by the way is 8795 members strong (!), an important vacuum processing question was recently asked and what follows is a stimulating exchange of ideas,[...]
Vacuum Diffusion Bonding – by Design
Many of us who use vacuum furnaces are all too familiar with and have learned how to counteract the unintentional diffusion bonding that has been known to occur between component parts exposed to high temperatures and low vacuum levels.1
By contrast,[...]
Evaporation
When performing any type of vacuum heat treatment it is always important to be aware of the possibility of evaporation and/or sublimation of elements, which can be present in the material being processed, introduced into the vacuum system with the[...]
Vacuum Deposition Processes
Vacuum deposition is a generic term used to describe a type of surface engineering treatment used to deposit layers of material onto a substrate. The types of coatings include metals (e.g., cadmium, chromium, copper, nickel, titanium) and nonmetals (e.g., ceramic[...]
A Layman’s Guide to Understanding The Theory of Gases
The movement of gases is an important and interesting subject but one often dismissed as a topic best left to scientists. However, the Heat Treater needs to know something about the basic nature (theory) of gases and in particular how[...]
Vacuum Brazing with Dan Kay
Kay & Associates Brazing Seminars
Since brazing plays an important part in some of your company’s products, plan to have one or more of your people attend one of the high-powered, three-day (Tues-Thurs) seminars being held in 2019. Contact your people today to have them[...]
Can Brazing Stop-Off Usage be Abused?
This topic has surfaced again in one of my client’s brazing shops, as brazing personnel encountered a brazing problem actually caused by the misuse of a brazing “Stop-off” in their braze-prep area. As the name of this product-type indicates, a[...]
Are Recessed Braze-Fillets Okay?
This question comes up frequently and needs to be addressed again. As shown in Figure 1, the brazing filler metal (BFM) has filled the inside of the tubular joint but has a slight recess at the top edge of the[...]
Revisiting Refrigeration of Brazing Paste. Is Refrigeration Really Necessary?
A number of years ago I wrote an article about the question of refrigerating brazing paste, something that has caused real problems for a number of people in the brazing industry, and which is still doing so today. A recent[...]
Vacuum brazing of EGR Coolers
Exhaust Gas Recirculation (EGR) coolers have been used extensively for many years on diesel truck engines, and are now also being used on gasoline engines. EGR coolers are specialized heat-exchanger assemblies that make extensive use of furnace-brazing (usually vacuum brazing)[...]
Vacuum Pump Technology: Education and Training
Proper Selection and Use of Vacuum Gauges
Selecting the correct vacuum gauge or gauges is critical to the success of a heat treatment process. It is important to know how they work and what options are available so that the correct choice can be made. There are[...]
Dry Pumps: Screw Type
Dry pumps are becoming increasingly popular as an alternative to oil sealed rotary vane pumps for many medium and high vacuum applications (e.g., in low-pressure vacuum carburizing where fine granular soot is carried from the process into the pump). Designers[...]
The Rotary Vane (RV) Vacuum Pump Turns 25
The Edwards “RV” (simply meaning Rotary Vane) laboratory sized oil sealed rotary vane vacuum pumps (Fig. 1) have been in the market for 25 years. They have a very unique design with no equal. This article will attempt to show[...]
The Oil Sealed Rotary Vane Vacuum Pump - Background and Designs
Vee belt drive design
This article discusses one and two-stage “medium vacuum” oil sealed rotary vane vacuum pumps that can produce a catalog ultimate vacuum of about 1 x 10-2 Torr (0.01 Torr or 10 microns) for a one stage model[...]
Five Main Reasons for using Vacuum
Fig. 1 Lifting with the aid of Suction Cups.
In this article, we're going to take a step away from vacuum pumps and systems and write about general applications that use vacuum in the process.There may be some applications you have[...]
Metallography with George Vander Voort
Metallography of Iron-Nickel Meteorites
Abstract
Figure 1: View of the Canyon Diablo meteor crater facing west in Coconino County, Arizona. The crater is approximately circular in shape. About 30 tons of specimens are in collections all over the world making it the most widely studied[...]
Microstructure of Isothermally-Treated Steels
Introduction
The microstructure of iron-based alloys is very complicated, being influenced by composition, homogeneity, processing and section size. Microstructures in coarse-grained steels are much easier to observe than in fine-grained steels. Of course, steels are normally made with a fine grain[...]
Conducting the Failure Examination
Failures in metallic components may be caused by any of the following factors or combinations of factors:
Design shortcomings
Imperfections due to faulty processing or fabrication
Overloading and other service abuses
Improper maintenance and repair
Environmental factors
Not all failures are[...]
Identifying the Cause of Tool and Die Failure
Abstract
Tool Steel Failure Examples and Metallographic Imagery below.
Steels used for tools and dies differ from most other steels in several aspects. First, they are used in the manufacture of other products by a variety of forming processes. Second, tools and[...]
Metallographic Examination of Medical Implants
Abstract
Medical technology has developed many new devices that can be implanted into humans (in-vivo) to repair, assist or take the place of diseased or defective bones, arteries and even organs. The materials used for these devices have evolved steadily over[...]