Modified Prototypes of Rotary Arm–Type Test System Using a Small Ball Probe for Determination of Cooling Characteristics of Quenchants

Abstract

Performances of quenchants have been enhanced and maintained based on their cooling characteristics as determined by specific test systems. A rotary arm–type test system with a small ball probe has been developed for this purpose by making prototypes. The unique concept, derived mainly from a circular motion of a small ball probe in quenchants, was proposed by Tawara in 1941. The prototypes have been realized by current heating, measuring, and mechatronic techniques. The material used for the probe has changed from nickel alloy to platinum to resolve the discoloration and thermal aging problems on the probe surface. The performance of the prototypes has been verified by systematic tests using specific quenchants under some cooling conditions.

A Brief Review on Test Systems Using a Ball Probe for Determination of Cooling Characteristics of Quenchants

“…17, identify meanings of each cooling situation. When comparing the results of this test with those of the same condition in the third prototype of the rotary-arm type [11], it was revealed that temperatures when the collapsing vapor film were different. Inverse Heat Conduction Problem of a Ball Probe The program IHCP1D [29] for the numerical solution of onedimensional inverse heat conduction problem was applied to evaluate heat transfer coefficients at the probe surface.…”

“…The author's group has developed prototypes of test system using a small ball over phases [9,11,12] based on the concepts of previous systems. The rotary arm type was selected initially for the prototype based on Tawara's concept.…”

“…The author's group has developed prototypes of the test system using a small ball probe since 2011, initially which was performed to reproduce the concept of Tawara's apparatus [10]. Then a rotary-arm to transfer and immerse a probe was installed in the system, which is called a rotary-arm type, was developed in three phases of this project [11]. Currently, a mechanism to elevate a quenchant container with respect to a stationary probe and to cool it has been devised, which is called an elevator container type [12].…”

A Brief Review on Test Systems Using a Ball Probe for Determination of Cooling Characteristics of Quenchants

“…The authorÕs group has been developing prototypes of the test system using a small ball probe over phases ( Ref 9,11,12) based on the concepts of previously developed systems. The rotary arm type was selected initially for the prototype based on TawaraÕs concept.…”