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A. Shanyavskiy, Frattura ed Integrità Strutturale, 25 (2013) 36-43 ; DOI: 10.3221/IGF-ESIS.25.06 41 known tests this effect has been demonstrated [2]. Horizontal line shows cascade of crack increments with constant value. Indeed, it cannot be exactly calculated values on constant increments but they evidently exist. It needs to point out that during external stress level increasing there is in matrix process deformation with different value of elastic modulus for different areas in metals. That is why in matrix there will be different areas where plastic deformation will be realized. Difference in value of local yield stress under the same external stress level, for instance, for polycrystalline aluminum can be more than 1.5 times at the moment of its start. Under cyclic loading there will be difference in local stressing metals during uploading portion and unloading portion in each cycle because exist difference in elastic modulus for tension and compression too. Moreover, the problem of specific environment low pressure for subsurface cracking shows that the (  K eff ) e which has been used for crack growth rate calculation, ought to be diminished on the factor Ce=(  K eff ) e /(  K eff ) se <1, where (  Keff) se is the stress intensity factor in environment with low pressure that at the one atmosphere. This consideration based on many test results that can be taken from review [21]. Summarizing performed briefly discussion of non-conventional metals subsurface fatigue cracking it ought to introduce corrections in Paris-Hertzberg [1] equation in the next form: 1/2 3 / [ / ( ) ] q e eff q da dN a C K E a   (7) For metals it should be considered physically quant of fracture a q ≥2b. Parameter C e = (  K eff ) e /(  K eff ) se <1 has to be estimated for all metals applicably to results of fatigue cracking in vacuum and in environment. Next point, that ought to be discussed, for process of subsurface matrix cracking is related to slope in Paris-Hertzberg equation (1). Earlier it was shown that for low range of crack increments in one cycle being less than 10 -7 m/cycle, average value of crack growth rate can be considered under the load constant condition by the same manner that it is under constant deformation [21]. From this consideration follows that subsurface cracking takes place with slope in Paris- Hertzberg equation equals “2”. This value of slope has been discovered in steels based on fatigue striations measurements for subsurface crack propagation [8]. The striation spacing interval was in the range of (0.1-2.0)x10 -6 m. In this investigation has been discussed this situation and the discovered slope was equal “2” related to crack opening effect with cyclical plastic zone. From the performed above consideration of subsurface crack propagation follows that it can be considered Paris equation in the next form: 2 / ( ) o eff da dN C K   (8) The value of a q has consideration at the threshold stress intensity factor, ( ) eff th K  . That is why C 0 in Eq. (8) can be considered as 2 0 / ( ) q eff th С a K   . At the end we can conclude that 2 / ( /[ ] ) q eff eff th da dN a K K    (9) In the case of circular subsurface crack growing [10] the stress intensity factor formula is: 1/2 (2 / ) [ ] K a       (10) Substituting (10) in (9) we can obtain simply equation: 0 / ( / ) q c da dN a a a  (11) In Eq.6, a 0 -value determines crack length at the FGA border with crack increment a q , a c -value determines maximum length of subsurface crack. This equation can be considered for failure analyses because there is not need in special knowledge of stress level or environment effect during subsurface cracking. Calculated number of cycles by the formula (11) will be always less than real subsurface cracking period because FGA zone creation with spherical particles formation cannot be expressed in fracture mechanics terms. C ONCLUDING REMARKS . New mechanism of fatigue crack subsurface origination was considered for metals with Fine-Granular-Area forming. First, this pattern has result of material hydrostatic pressing and rotation that directed to appearance ultra- high-plasticity in a local volume with nano-structure performing. Second, fatigue cracking develops by the border of 1