State and Development of the RIAR Techniques for In-Pile Investigation of Mechanical Properties of Materials and Products for Nuclear Engineering A.Ya. Rogozyanov, R.R. Melder, А. А. Nuzhdov, S.V. Seredkin and V.A. Starkov FSUE “SSC RIAR”, Dimitrovgrad, Russia

1. Investigation techniques of creep, deformability and long-term strength using the “Neutron” facilities The current state of the methods

Features of the “Neutron” Facilities

2. Investigation techniques based on relaxation tests 2.1. The UVIRIM Facility Current State of the Techniques КН СИ СПН ОУ ДТП САРТ СУ

Features of the UVIRIM Facility

2. Investigation techniques based on relaxation tests 2.1. The URIP facility Aluminium block Springs Central core plane (CCP) Current State of the Techniques

Features of the URIP Facility

3. Investigation methods of creep, deformability and long-term strength under pressure Current State of Techniques 101  9,15  0,7 95 Specimen under test

Features of the UITO Facilities

4. Investigation techniques of dispersed fuel creep The URIPT facility Сurrent State of Techniques

Features of the URIPT Facility

Further development trends of in-pile techniques extension of temperature range for structural materials tests up to 1200 о С development of methods for creep test of high-burnup oxide fuel methodical support of the upgraded SM reactor core cells

THE UPGRADED SM REACTOR CORE Channel and its No. Shim rod Automatic control rod Emergency protec- tion control rod in the beryllium insert Core cell with a fuel assembly (FA) FA with experimental cells  12 mm FA with an experimental cell  25 mm Loop channel  68 mm

NEW POSSIBILITIES OF THE SM REACTOR UPGRADING OF THE CORE TURNS THE SM REACTOR INTO THE MOST ATTRACTIVE REACTOR FOR MATERIAL SCIENCE INVESTIGATIONS, INCLUDING STUDIES ON LONG-TERM MECHANICAL PROPERTIES: - extension of the fast (up to 2  сm -2 s -1 ) and thermal (up to 3  сm -2 s -1 ) neutron density range and damage dose (up to 25 dpa/year), being superior to the same BOR-60 parameters - wide temperature range ( о С) of high-flux irradiation in water, boiling water, steam and inert gas environment - instrumentation of in-pile investigations on some material properties under continuous monitoring and control over temperature, load and strain - target pressurization of specimens with gas, tensile and compression loading, any combination of pressure and uniaxial loading, relaxation bending tests

CAPSULE IRRADIATION RIGS (IR) LOCATED IN THE SM CORE FOR TESTING AT 50 – 320 О С Boiling IR for testing tubes under pressure Unsealed IR in FA, cooled with primary water Boiling IR for testing specimens under longitudinal loading To the stand of high pressure  23,8 Therm. couple CCP Water Specimens К стенду высокого давления CCP Specimen Water To the stand of high pressure To the stand of high pressure  54 х 3 Strain gauge Loading gauge Separating sylphon Loading sylphon

POSSIBILITIES OF THE SM AND RBT-6 REACTORS regarding study on functional properties (strength, ductility, irradiation-thermal creep, radiation growth) in in-pile irradiation conditions and on their relationship with material structure

POSSIBILITIES OF THE SM AND RBT-6 REACTORS

Specimen gas pressurization rig booste r Air P р =0.6 MPa He P р ≤ 15 MPa to PC MIDA РД - high pressure valve, Р н =20 MPа; - low pressure valve, Р н =2.5 MPа; The rig provides pressure up to 100 MPa (DHC, creep, long-term strength), possibility to model DНС of claddings at high burnup values. The rig needs to be equipped.

COMPREHENSIVE TECHNIQUES FOR IN-PILE INVESTIGATION OF MECHANICAL PROPERTIES IMPACT FACTORS: NEUTRON FLUX AND FLUENCE (DAMAGE DOSE AND RATE), TEMPERATURE, LOAD, LOAD TYPE, TEST CONDITIONS, ENVIRONMENT CYCLIC TESTS LOW / HIGH-CYCLE FATIGUE Under development STATIC AND QUASI-STATIC TESTS CREEP, DUCTILITY, LONG-TERM STRENGTH, DEFORMABILITY RELAXATION ABILITY SCC, DHC under development UITO PRESSURIZATION (SM, RBT-6, BOR-60, SM core) NEUTRON TENSION COMPRESSION PRESSURE (RBT-6, SM) URIPT COMPRES- SION (SM) UVIRIM BENDING ( RBT-6, SM) UITO(I) PRESSURIZATION (SM, RBT-6) URIP TWISTING (RBT-6) NEUTRON TENSION (SM, RBT-6) UITO PRESSURE (SM, RBT-6) ARS

CHARACTERISITCS OF IN-PILE INVESTIGATION METHODS OF MECHNICAL PROPERTIES NUMBER OF SPECIMENS IN IR : under longitudinal loading 1-2 under bending or twisting 1-25 under pressurization or swelling composition up to 20 NEUTRON FLUX DENSITY, cm -2 s -1 : fast (Е  0,1 МeВ)  thermal DAMAGE DOSE ACCUMULATION RATE, dpa/year 0,2-25 MAXIMAL UNIAXIAL LOAD, kN 5 (  1%) MAXIMUM PRESSURE IN TUBULAR SPECIMENS, MPа 100 (  1%) PRESET DEFORMATION RATE, %/hr (  5%) TESTING TEMPERATURE : in water under pressure о С (  1%) in boiling water о С (  1%) in water with supercritical parameters о С (  1%) in helium о С (  1%)

CONCLUSIONS ON THE METHODICAL POSSIBILITIES OF THE RIAR REACTORS THE REACTORS AND THEIR METHODS MAKE IT POSSIBLE: to determine radiation stability of basic materials under modeled operation conditions of nuclear reactor materials at high fuel burnup, specific loading types and thermal- force modes to provide reliable validation of the main criteria (creep, radiation growth, short-term properties, long-term strength) for the choice of the most promising new reactor materials to develop databases for creation adequate models of operation parameters of selected alloys as applied to calculation codes