
The High Temperature Corrosion Laboratory was established to provide a facility to conduct experimental research on corrosion, stress corrosion cracking (SCC), and hydrogen embrittlement experiments in high temperature aqueous and gas environments and, in particular, simulated light water reactor environments. The corrosion laboratory has unique facilities for conducting both high and low temperature corrosion, stress corrosion cracking experiments, electrochemical tests and mechanical tests. The HTCL consists of six refreshed autoclave systems (titanium, Inconel, or stainless steel construction), five mounted in constant extension rate (CERT) machines and one in a constant load machine.
Experiments can be done in a wide range of environments, including supercritical water, simulated BWR and PWR water, high temperature steam, and gas environments. Each autoclave is isolated from the other systems with independent water and computer monitoring systems. The lab also contains two full-featured corrosion measurement systems and two additional potentiostats.
Monitoring & Safety
The testing systems in the High Temperature Corrosion Laboratory use programs developed with the National Instruments LabVIEW software package to measure the conditions during a test and to control some parameters (such as strain rate). The program is used in tandem with data acquisition boards to read measurements sent by instruments in the system such as thermocouples, conductivity meters, LVDT’s, Load cells, and pressure gauges. Temperature, pressure, conductivity are recorded continuously for future reference. The load on each sample as well as total extension are also recorded.
An important safety feature of the system is that LabVIEW can send email and/or text messages when experiment variables stray out of normal/safe range. Using this capability, the user can set system upper and lower limits for different parameters, usually for temperature and pressure. If a reading exceeds these bounds a text message is sent to a digital pager or cell phone, alerting the researcher of a problem and the nature of the problem within seconds. Since most tests can last up to a month and beyond and have conditions that would be dangerous if uncontrolled, this is a very valuable system for problem solving and prevention. Further, this system protects the safety of the laboratory personnel and equipment as well as the integrity of the data.
HTCL Experimental Capabilities
System
System 1: Multi-Specimen Super Critical Water (MSCW)
- 4 Liter Inconel 625 Refreshed Autoclave
- Max Pressure: 30MPa @ 600°C (4350psi @ 1112°F)
- Multiple Specimen CERT Experiments
- Corrosion Coupons (up to 8 Specimens at a time)
- Mixing Column for water chemistry control
System 2: Single-Specimen Super Critical Water (SSCW)
- 2 Liter Inconel 625 Refreshed Autoclave
- Max Pressure: 34MPa @ 550°C (5000psi @ 1020°F)
- Single Specimen CERT Experiments
- Corrosion Coupons (up to 48 Specimens at a time)
- Mixing Column for water chemistry control
System 3: Multi-Specimen CERT-1 (CORTEST)
- 2 Liter Titanium Grade 5 Refreshed Autoclave
- Max Pressure: 17MPa @ 343°C (2500psi @ 650°F)
- Multi-Specimen CERT Experiments
- Mixing Column for water chemistry control
System 4: Multi-Specimen CERT-2 (KORRODATA)
- 2.5 Liter Titanium Grade 2 Refreshed Autoclave
- Max Pressure: 20MPa @ 365°C (3000psi @ 689°F)
- Multi-Specimen CERT Experiments
- Mixing Column for water chemistry control
System 5: Multi-Specimen Creep
- 2 Liter 316 Stainless Steel Refreshed Autoclave
- Max Pressure: 22MPa @ 371°C (3300psi @ 700°F)
- Creep Experiments
- Mixing Column for water chemistry control
System 6: Single-Specimen Steam
- 1/4 Liter 304 Stainless Steel Vessel
- Max Pressure: .14MPa @ 400°C (20psi @ 752°F)
- Single & Multi-Specimen CERT Experiments
Environment
Supercritical Water
Experiments can be performed in two supercritical water autoclaves.
- Up to 600°C
- High-performance liquid chromatography pump provides flow rates up to 100 mL/min at up to 27.5MPa
- Water conductivity monitored at the inlet and outlet
- Dissolved Oxygen monitored at the inlet and outlet to 5 ppb
- Water chemistry control via mixing column
Light Water Reactor Environments
Experiments can be performed in two CERT systems in simulated BWR or PWR environments.
- Water temperatures at 288-360°C
- Water conductivity
- Monitored at the inlet and outlet
- Controlled via dilute acidic solution in mixing column
- Dissolved Oxygen
- Monitored at the inlet and outlet
- Controlled from 8 ppm down to 1 ppb
- Additions of boric acid and lithium hydroxide to simulate PWR environment
High Temperature Steam
Single specimen CERT tests can be performed in a high temperature steam environment.
- Steam temperatures up to 550°C
- Desired corrosion potential can be obtained by controlling the H2/H2O partial pressure ratio
- Hydrogen partial pressure is controlled using custom Ar/H2 gas mixtures and a mass flow controller
- Water vapor partial pressure is controlled using a steam bath in combination with dew point meters
Constant Load Testing
Creep tests can be performed in a two-liter constant load system. This system allows for simultaneous testing of three samples under controlled load conditions.
- Simulated BWR or PWR conditions (288-360°C)
- High temperature gas (550°C)
- Creep rates lower than 10-9 s-1 can be reliably measured