@ To Previous Page(circulation)To Next Page


*FREE-Vib. YOUNG'S-Modu. METER *


ƒƒ‚i‚d-‚q‚sA‚i‚d-‚g‚s„„

Free resonance vibration type equipment to measure Young's modulus and internal friction

‚i‚d-‚q‚s with Rod Sample

OUTLINE of THE EQUIPMENT

This equipment is specified to measure the Young's modulus and internal friction ) using the free resonance vibration method. Since the free vibration method keeps the specimen at the vibration nodes without any restraint, errors from individual difference and repeated measurements can be minimized and, accordingly, it is characterized by the excellent reproducibility of the data. In the ordinary resonance method employing the "suspension wire tehnique", the specimen is almost freely suspended by two thin wires near the vibration nodes, one of which transfers the applied vibration signals and the other picks up the induced vibration of the speciman. Therefore, the vibration of the specimen is not a pure free vibration in the rigorous sense. This will not produce any disturbance in the practical elasticity measurement but give rise to an undesirable high background in the high precision measurement of internal friction. In our equipments of the JE series, the eletrostatic Coulomb force is used for driving the vibration and an acoustic method is used for detection of the specimen's vibration (a patent by Osaka Univ./ Sumitomo Electr.), which are perfectly contact free. The specimen is held on two thin wires at the exact vibration free node positions, which gives no influence at all to the free vibration of the specimen. This technique enables such a high precision measurement that the resolution reaches down to three places of decimals in the frequency of the order of some thousands Hz in the Young's modulus measurement. In the JE series with such a high precision and very low outer disturbance, detection of very smallest change of resonance frequency is possible and, therefore, applicable to the measurement of Young's modulus of thin films and analysis of a small change of concentration of a component in alloys and compounds. Especially, our equipments are outstanding in the measurement of internal friction as small as 1~10-4 or less and the calculation of its activation energy, both of which require the exact absolute values of the data. The driving system and the detecter circuit originally developed by us are powerful enough and wide frequency ranged so that not only the slabs but also the bars with round or triangular cross section can be measured. Wide range on the sizes and weight exist too. This means that many kinds of specimens are measurable if they are in the shape of a straight and uniform bar with a certain solid cross section. Setting up of the specimen is extremely easy , only requiring "placing it on the thin wires", and this assures of the high precision performance. We are sure that, among other free resonance machines, our JE series is distinguished in the multiplicity in functions and the easyness in operation. There are three types in the JE series; JE-RT is a compact, computer built-in type exclusively for room temperature measurement, JE-HTm is a high temperature manual type, which requires manual opertion in temperature setting and measurement, and JE-HT is a computer controlled automatic high temperature type. Generally speaking, the free resonance type machines need the highest skill and understanding in operation, since the measurement sometimes becomes difficult at high temperatures above 600Ž.


Therefore, the bases of the use of JE series are set up as follows.

           ž Only for the measurement of Young's modulus
           ž Temperatures required are relatively low ( below 500~600Ž )
           ž When the high precision measurement is required
           ž For the specimens of various shapes
This series will be the best choise when meeting to the above conditions.

The compact and low price part for room temperature measurement can be used for the precision calibration of the EG-HT equipments for high temperature use.

Standard Specifications


   Method of measurement: free holding characteristic vibration type
   Driving system: contactless electro-magnetic driving
   Range of applied vibration frequency: 300Hz ~ 10,000Hz
   Detection system: by contactless detection of vibration sound
   Range of detectable frequency: 600Hz ~ 20,000Hz
   Materials to be measured: metals, ceramis, high polymers, glass, bricks,
       		and etc.
   Standard specimen size:           (in mm units)
          JE-RT:slab of 30~150L ~ 3~19W ~ 0.8~5T 
                rod  of 30~150L ~ 1~19ƒΣ
          JE-HT:slab of 30~70L ~ 3~19W ~ 0.8~5T 
                rod  of 30~70L ~ 1~19ƒΣ
   Electric furnace for JE-HT: maximum temperature; 1000Ž (special order
for higher temperature use is possible) OptionsFThe measuring part of another series equipment can be attached. Optional attachment of other functions and inquiries on other kinds of improvement are welcome.

To Next Page

To Cover Page

Please send us the questions, asking catalogue and/or estimation using next crick.
Mail to Us

Renew at 97/8/26


Nihon Techno-Plus Co.,Ltd(NTP)