PRESENTATION

The project will involve Pr. Bernard's team within the Interdisciplinary Carnot Laboratory in Burgundy (ICB, UMR 6303 CNRS-UBFC), the Innovation Laboratory for New Energy Technologies and Nanomaterials of the CEA in Grenoble, the Center for Shaping of materials (UMR 7635 CNRS-Paris Sciences Lettres / Mines ParisTech) and the company Framatome. This partnership provides the CALHIPSO project with a rich scientific environment and complementary equipment both from the point of view of manufacturing processes and that of characterization means.

• CALHIPSO platform

Frédéric BERNARD

MANAGER

Frederic.Bernard@u-bourgogne.fr
Phone : 03 80 39 61 25

We have two flash sintering machines or SPS (Spark Plasma Sintering). This relevant process allows the densification of all types of powdery materials (metals, ceramics, composites, etc.). Our machines make it possible to subject the sample to a high intensity electric current (typically 0-10V, 1-30 kA) while applying a pressure of several tens of MPa and, this, in a temperature range varying from ambient up to 2400°C.

• HPD-125 (Manufacturer: FCT Systeme GMbH) ø = 30mm - 160mm, h = 60 - 80mm, 2400°C, 1250kN, 600°C/min, vacuum, neutral atmosphere (argon, nitrogen), reducing atmosphere (hydrogen)
• HPD-10 (Manufacturer: FCT Systeme GmbH, Model: HPD 10) ø = 8mm-40mm, h=30-50mm, 2400°C, 100kN, 400°C/min, vacuum, neutral atmosphere (argon, nitrogen)
• Contact : S. Le Gallet, F. Bernard

{slide=Learn more about flash sintering}

Flash sintering presses are intended for shaping powders and/or assembling all types of materials. The objectives are industrial applications and/or studies to understand consolidation phenomena and/or interfaces.

The technology makes it possible to subject the sample to pulses of electric current while applying a uniaxial load and this in a temperature range varying from ambient to 2400°C. The treated samples can have, for the smallest machines, a diameter varying from 5 to 50 mm and can reach 400 mm for industrial equipment. The experiments are generally carried out under vacuum but it is however possible to work under controlled atmosphere (argon, nitrogen, hydrogen)

The flash sintering platform has two flash sintering installations, FCT system brand, one of small dimension called research, and another of larger dimension called development.

The functions common to our equipment are as follows:

• Servo-hydraulic force control
• Compression stroke and speed measurement
• Vacuum chamber made of double-walled special steel, water-cooled
• Temperature measurement and control optionally via axially and/or radially placed pyrometers and/or mobile thermocouples
• Freely programmable sintering parameters with up to 45 segments per recipe
• Variable on/off pulse programmable (1...255 ms) separately for each segment
• Comprehensive software for data logging and analysis of all sintering parameters

{/slide}

{slide=All the features of the HPD 125}

• Compressive force: 20...1250 kN
• Piston stroke: 0...150 mm
• Piston movement speed: 0...2 mm/s
• Max sample diameter Ø: 150 mm
• Max mold dimensions: Ø 350 x 400 mm
• Maximum temperature: 2400°C
• Max temperature ramp: 5...1000°C/min (depending on tool size and target temperature)
• Vacuum in enclosure: 5 x 10-2 mbar
• Pressure: 0-1100 mbar
• Cooling system water flow (4 bar): 8 m3/h
• Max voltage: 8V
• Max intensity: 24000 A
• Maximum power: 37 kW
• Pulse duration ON: 1...255 ms
• Pulse duration OFF: 0...255 ms
• Number of pulses: 1...255
• Extra Pause: 0...255 ms
• Equipment dimensions (w/d/h): 5000 x 2000 x 3200 mm
• Weight: approx. 5000kg
• Electrical specification: 3 x 400 V, 50 Hz, 300 kVA
• Working atmosphere: Ar and N2 or pure H2 (specific to the equipment)
• Regulation: Axial, radial pyrometer, K thermocouple or S thermocouple with the possibility of having 10 simultaneous measurement points (specific to our equipment)

{/slide}

{slide=All the features of the HPD 10}

• Compressive force: 20...100 kN
• Piston stroke: 0...100 mm
• Piston movement speed: 0...2 mm/s
• Max sample diameter Ø: 40 mm
• Max mold dimensions: Ø 120 x 100 mm
• Maximum temperature: 2400°C
• Maximum temperature ramp: 5...400°C/min
• Vacuum in enclosure: 5 x 10-1 mbar
• Pressure: 20-60 mbar
• Cooling system water flow (4 bar): 2.5 m3/h
• Max voltage: 7.2 V
• Max intensity: 5500 A
• Maximum power: 37 kW
• Pulse duration ON: 1...255 ms
• Pulse duration OFF: 0...255 ms
• Number of pulses: 1...255
• Extra Pause: 0...255 ms
• Equipment dimensions (w/d/h): 1000 x 800 x 2200 mm
• Weight: approx. 1000kg
• Electrical specification: 3 x 400 V, 50 Hz, 45 kVA
• Working atmosphere: Ar and N2
• Control: Axial pyrometer or K thermocouple

{/slide}

HIP

We also have a hot isostatic compression machine (CIC) which makes it possible to obtain massive materials of complex shapes from metallic or ceramic powders by applying a high pressure of argon. This device also makes it possible to assemble solid parts of a different nature by diffusion welding. Pressure and temperature ramps can be selected independently

HIPress: QIH 15L (Avure), enclosure dimensions: ø = 186 mm, h = 500 mm, temperature rise up to 2000°C (rise rate up to 50°C/min), pressure up to at 2000 bar.

• Contact : J-P. Chateau-Cornu, F. Bernard

Planetary grinder

Mechano-synthesis is the operation which allows the synthesis of an alloy within a crusher thanks to a succession of fracture and welding operations. Unfortunately, this mechanical grinding requires long grinding times leading to contamination of the powder by the grinding tools. However, it is possible to carry out a mechanical activation via the use of short-term high-energy grindings (P4, Fritsch), it makes it possible to produce nanostructured aggregates or agglomerates. Thus, to obtain the desired alloy, it will be necessary to apply a heat treatment to the mixture of mechanically activated powders. This mechanical activation will reduce the annealing and sintering temperatures due to the reduction in grain size but also the accumulation of defects.

• P4 Planetary Mill (Fritsch), Jars from 12 mL to 500 mL, Rotation speed from 0 rpm to 400 rpm
• Contact : F. Bernard

The ICB laser hall located in Le Creusot implements laser processes (welding, cutting, marking), as well as more conventional arc welding processes.

The know-how acquired over 25 years has made it possible to develop a multidisciplinary (thermal, hydrodynamic, mechanical, metallurgical, physico-chemical) and multi-scale approach, making it possible to understand the phenomena that occur during the interaction of the energy beam with matter, and the effects induced by this interaction.

The activity combines the experimental aspects:

• Process optimization (experimental plans)
• Process instrumentation (rapid imaging, thermometry, thermography, DIC image correlation, physico-chemical and mechanical characterizations)

With multi-physics numerical simulations:

• Thermo-hydraulics: modeling of laser welding in keyhole mode (formation of the capillary, etc.) / modeling of electromagnetic couplings in arc welding
• Thermomechanical: modeling of the formation of stresses in assemblies in order to understand the phenomena and control their consequences, to answer scientific questions but also industrial issues.

The board has several laser sources including:

• • TRUMPF TRUDISK 6001: continuous Yb-YAG laser (1030 nm) with a maximum power of 6 kW (minimum 100 µm fiber), used in welding
  • TRUMPF HL304P: pulsed Nd-YAG laser (1064 nm) with a maximum average power of 330 W (9 kW peak), used in particular for cutting
  • ROFIN SLM40D: pulsed Nd-YAG laser (1064 nm) with a maximum average power of 40 W (61 kW peak), used for marking as well as conventional welding processes: including TIG, MIG and CMT (Cold Metal Transfer) .

At the numerical calculation level, it is mainly based on COMSOL, ABAQUS and ANSYS commercial software.

The articulation with the socio-economic world is done via SATT SAYENS.