Proxima – microMECHA

Introduction

PROXIMA brings high quality material testing to your scanning electron microscope. Its unique and compact design allows to perform tensile, compression, 3- and 4- point bending and biaxial testing during EBSD analysis. You achieve high resolution images through its optimised design allowing screen-to-sample and working distance below 18 mm.

PROXIMA is capable of performing different kind of tests:
– Tensile / Compression (EBSD compatible)
– 3-points bending (EBSD compatible)
– 4-points bending (EBSD compatible)
– Biaxial (EBSD compatible)

Our software provides the flexibility of control, data processing and analysis to meet your needs.
– Manual testing, controlling the speed and direction of the displacement
– Targeting force, controlling the speed by targeting a desired force
– Targeting displacement, controlling the speed by targeting a desired displacement
– Cyclic testing, controlling the number of tensile-compression cycles using values in force or displacement

Designed to perform a full spectrum of standard and unique tests across a wide range of materials.
– Metals
– Ceramics
– Polymers
– Textiles
– Etc.

Technical Features

Test	Tensile, Compression, Bending, Biaxial
Force capacity	3.5 kN
Dimensions	185 x 86 x 56 mm
Weight	1.7 kg
Crosshead travel	15 mm (for a sample of 50mm)
Max. speed test	50 µm/s
Min. speed test	0.1 µm/s
Displacement sensor	Resolution of +/- 20nm
Force sensor	Linearity < +/- 0.25 of F.S. Hysteresis < +/- 0.25 of F.S.

EBSD compatibility	Yes
Working distance	12 mm
Sample-to-screen distance	Camera centred on the sample 12mm Camera scanning the sample 18mm

Different clamping systems for tensile/compression, 3- or 4- point bending and biaxial testing are available for SEM and EBSD applications
Unique design optimized to perform EBSD analysis under best circumstances (reduced working and sample-to-screen distances)
Reduced geometries allow to position the machine inside most environments (SEM, X-ray diffraction, synchrotron radiation, etc.)
Increased efficiency using state-of-the-art technology in mechanical transmission, working on a speed range between 0.1 – 50 µm/s and a force up to 3,5 kN.
Increased rigidity by coupling precise guiding and transmission systems.
Excellent precision on the displacement (accuracy of 20nm) and force measurements (linearity and hysteresis below 0.25% of the full scale).

Mechanical and electronical security allow to protect the user and the micromachine from any damages, as well as the complete automatisation of the ongoing tests.
The applied forces are on the same plan than the testing sample, eliminating any bending moments.

The software has been developed based on today’s requirement in research and development. The major tests, as tensile, compression and bending, can be performed with the same machine.

Accessories

3- or 4- point bending grips (EBSD compatible)

3- and 4-point bending grips allows to image the ‘edge-on’ of the sample, either during conventional observation (0° tilt of the sample), or during EBSD observation (70° tilt of the sample). The dimensions and space between the clamps can be adapted to your need.

Biaxial grips (EBSD compatible)

Biaxial testing generates more precise simulations of real-world stress states. Therefore MicroMecha developed the first biaxial grips which are also EBSD compatible, allowing complex multiaxial stress simulations. Specimen are typically cruciform.

Heating & Cooling stages

Our heating and cooling stages allow to combine thermal and mechanical applications. Both can be aimed at either conventional observation (0° tilt of the tensile sample) or EBSD observation (70° tilt of the tensile sample). The spectrum of temperature lies between –180°C and 450°C.

Interchangable load cells

Since not all applications are alike, additional load cells are available to extend the load range of Proxima. These can easily be switched by the user, guaranteeing a maximum of flexibility.

EBSD

PROXIMA’s design allows you to perform pure tensile/compression tests, as well as 3 and/or 4 point bending tests and biaxial tests up to 3kN.

Each test can be performed during EBSD analysis, achieving very low sample-to-screen and working distances.

Diffracted cone for tensile/compression sample

Diffracted cone for 3- or 4-point bending sample

Diffracted cone for biaxial sample

Smaller WD (working distance)

A shorter WD creates a pattern center near the top of the phosphor screen so that the diffraction intensity is uniform and the Kikuchi lines are in focus. The upper structure of PROXIMA has been optimized to reduce the working distance between the pole piece of the scanning electron microscope and the testing sample.

Unlike conventional designs, the 70° tilt is not performed on the entire machine, but is limited on the clamping sample. This educes any premature collisions between PROXIMA and the pole piece of the SEM, thus achieving WDs of 12mm.

Smaller SSD (screen-to-sample distance)

The quality of the recorded patterns depend on the sample-to-screen distance, as the signal intensity will fall with distance. If the screen is moved further away from the sample, the signal will decay requiring a more sensitive low light level camera or increased integration time.

Unlike traditional testing devices with two columns on each side of the testing sample, the new PROXIMA relocates this mechanism behind the testing sample. Reducing the number of ball screws allows to open an area on one side of the sample. As a result, the phosphor screen of the EBSD detector can achieve SSD

Diffracted cone for tensile/compression sample

Diffracted cone for 3- or 4-point bending sample

Diffracted cone for biaxial sample