IQ Technologies Inc. Akron, USA Transient Nucleate Boiling as a Law of Nature and a Basis for Designing of IQ Technologies Nikolai I. Kobasko Intensive Technologies Ltd, Kyiv, Ukraine IQ Technologies Inc. Akron, USA WSEAS THE’09 August 20 - 22, Moscow

Introduction Why is important to evaluate duration of transient nucleate boiling process? IQ technological processes save materials, increase service life of steel parts, improve environment, decrease cost of products. Designing of equipment for IQ processes. Transient nucleate boiling processes exist in the Nature independently on will of people Equation for calculating duration of transient nucleate boiling process

Fully-Automated IQ System

Continues Technological Line

Results of IQ Simulation Showing the Development of a Uniform Hardened Case

Sleeping Volcano

Erupted Volcano

The Duration of the Transient Nucleate Boiling Process (1968 – 1969) is duration of transient nucleate boiling depends on initial temperature of a steel part and condition of cooling depends on configuration of steel part depends on liquid flow velocity; D is size of steel part (m); a is thermal diffusivity (m2/s)

Coefficient depending on initial temperature and properties of the quenchants Water, 20oC 4.17 30-50% CaCl2 4.78 5 – 12% NaOH 3.6 6 – 8% Na2NO3 3.76

Coefficients for bodies of different shapes Shape of a body Equation Plate 0.1013 Cylinder 0.0432 Sphere 0.0253 Round plate (Z and D = nZ; n = 1 0.0303 n = 2 0.0639 n = 5 0.0926 ------ Finite cylinder D and Z = nD; -------- 0.0391 0.0425 -------

Mathematical Model for Evaluation of DTNBP The equation of transient heat conductivity is given as And boundary condition during nucleate boiling can be written as: Duration of transient nucleate boiling process is evaluated from the condition:

Duration of the Transient Nucleate Boiling Process (1979 – 1980)

Equation for Calculation the Cooling Time of Steel Parts (1969)

Kondratjev Form Factor K for Gear Drawing K, m2 p 73.310-6 2.9

Kondratjev Number vs. Fourier Number for Cylinders 15 - 60 mm

Average Generalized Biot Number is the Same for Different Sizes

Connection between Equations Biv = idem; Kn = idem;

Experiments on Quenching Made by French in 1928 (Probes)

Temperature vs. Time during Quenching of 38 mm Sphere in Cold Water (French in 1928) 1 Core 2 Surface

Heat flux density vs. time during quenching the spheres of 6 Heat flux density vs. time during quenching the spheres of 6.35 mm (a) and 12.7 mm (b) in diameter in 5% water NaOH solution

Duration of Transient Nucleate Boiling Process

Delay of Martensite Transformation by Adjusting Pressure

HTMT and LTMT to Produce Very High Density of Dislocation

Incorrect (a) and Correct (b) LTMT Process

Strength as a Function of Density Dislocation Where G is shear modulus

Optimal Quenched Layer in Steel Parts of Complex Configuration Where DI is ideal critical diameter; D is size of steel part; a is thermal diffusivity; is critical time from the CCT diagram

Punch Made of S5 Steel

Atmosphere Furnace Equipped with 41m3 Intensive Quenching Water Tank

Typical quenching system for quenching truck semi - axles

Service Life of Intensively Quenched Semi- Axles

SUMMARY Duration of TNBP is directly proportional to square of the thickness of a body and inverse proportional to thermal diffusivity of a material, depends on the configuration of the body, its initial temperature, velocity of a quenchant and thermal properties of the cooling system. On the basis of discovered regularities high strength materials were manufactured by use of intensive quenching. If used worldwide, new methods of quenching can improve environment, save materials, increase service life of steel parts, and reduce their cost.