A PROCESS DEVELOPMENT TOOL FOR THERMAL SPRAYING

Developed by Mattias OttossonStefan Björklund

© 2011

A module based system for real-time monitoring of for example:• Temperature• Strain• Displacement• Thickness

Typical areas of use• Temperature monitoring during pre-heat and cooling• Strain monitoring during and after spraying process• Monitor form changes of the component while it’s being processed• Development of new process windows

DATA FLOW

• Data are acquired before, during and after process• Data are being monitored and saved in real-time on a PC • Data can be interconnected with other common engineering

tools• Data can easily be compared to previous experiments

THE CONCEPT OF MODULES

The system contains besides the sample holding process altering or measuring fixture a number of different modules to meet the requirements of the process situation

The modules are• Media module, a rotating base with swivel system to feed air, water, electricity/signals to the system if needed• Electronics module, Signal conditioning and data acquisition, data transfer via WiFi• Computer and or Controller, saving and presenting acquired data, controlling process variables• Fixture with sensors or process altering device such as heater.

MEDIA MODULES

A rotating Swiveling device.• type 1. 18 channels of electrical power/signals (max 10A/ch) and 3 air/water lines, for example used as shop air supply and water in, water out to the unit mounted on media module

• type 2. 2 air/water lines, for example used as shop air supply x 2 or water in, water out to the unit mounted on media module • type3.(to be designed and manufactured)A low profile unit with only 18 channels of electrical power/signals, used with the heater unit where no internal cooling is needed

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ELECTRONICS MODULE

Heavy duty compartment to house sensitive data acquisition equipment. Acting as base for chosen process fixture thus keeping electronics away from the strong heat of the thermal process

• type 1. General battery powered configurable data acquisition system with WiFi transfer of data.Can be used stand alone with chosen process fixture or on top of swivel media module if cooling is needed.

• type 2.Signal conditioning for thermo couplers used for closed loop control of the temperatures in the electrical heating fixture.

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ELECTRONICS

• Changeable measurement modules for high flexibility• High channel count and sampling rates up to 250kS/s• Many different types of sensors can be attached• Wireless, encrypted data transfer using National Instruments WLS• Battery powered to handle rotation of fixture during process• Can be integrated into a real time control system

COMPUTER (MODULE)

Program application written to receive, present and control data from process module.

Output File Formats:• XML• CSV• Excel• Labview• MATLAB• Database SQL-server

CONTROL MODULE Control electronics, closed loop temperature control of Heater module

FIXTURE

• The fixture elements in this process development system is a part of our general module based multi sample-geometry fixture system.Measuring fixture elements can be combined with one or more general spray fixture modules, enabling data collection simultaneously with high quantity test sample spraying.

• Measuring fixture elements can be designed and manufactured for any desired test sample geometry.

• Measuring fixtures follows the same design practice as our general module fixture system, thus giving optimal economy, lifetime and protection by a system of replaceable wear parts.

SENSOR

• Virtually any type of sensor can with proper signal conditioning be put to work in this rotating telemetry process development system.

For example:• Laser distance measuring

single laser distance and dual laser distance differential measurement

• Temperature measuring pyrometer • Thermo coupler• Etc.

APPLICATION EXAMPLE

• Recording of substrate temperature during pre heating (with thermal spray torch) and multi layer of thermal spray. Recording max preheating temperature and actual-real preheating temperature after waiting for stabile flame-powder stream before first coating layer.

• Recording of substrate temperature history during spraying while applying different means of external cooling.

• Fixture and Electronics Module

APPLICATION EXAMPLE

• Controlled preheating of substrates during spraying, several different temperatures. spraying and then coating characterization of microstructure and adhesion.

• Possibility to get 3 different controlled temperatures out of each set of spray conditions, t1, t2 and unheated.

• Heating Fixture Electronics Module and Swivel Module.

Thank you for your time