A method for manufacturing a recovered steel sheet having an austenitic matrix presenting at least one mechanical property equal or above a target value M target whose composition comprises, in weight: 0.1 < C < 1.2%, 13.0 ≤ Mn < 25.0%, S ≤ 0.030%, P ≤ 0.080%, N ≤ 0.1%, Si ≤ 3.0%, and on a purely optional basis, one or more elements such as Nb ≤ 0.5 %, B ≤ 0.005%, Cr ≤ 1.0%, Mo ≤ 0.40%, Ni ≤ 1.0%, Cu ≤ 5.0%, Ti ≤ 0.5%, V ≤ 2.5%, Al ≤ 4.0%, 0.06 ≤ Sn ≤ 0.2, the remainder of the composition making up of iron and inevitable impurities resulting from the development, such method comprising the steps consisting in: A. a calibration step wherein: at least 2 samples of said steel having undergone heat treatments between 400 and 900°C during 40 seconds to 60 minutes, corresponding to Pareq values P are prepared, Pareq being defined by: Pareq = − 0.76 ∗ log exp ∫ − Δ H RT ∗ dt with ΔH: energy of diffusion of iron in iron (equal to 300 kJ/mol), T = temperature of the cycle in Kelvin, the integration being over the heat treatment time in hour, I. said samples are submitted to X-ray diffraction so as to obtain spectrums including a main peak whose width at mid height FWHM is being measured, II. M of such samples is being measured, III. the recovery or recrystallization state of each sample is being measured, IV. the curve of M as a function of FWHM is being drawn in the domain where the samples are recovered from 0 to 100%, but not recrystallized, B. a calculation step wherein: I. the value of FWHM target corresponding to the M target is being determined, II. the Pareq value P target of the heat treatment to perform to reach such M target is being determined and III. a time t target and a temperature T target corresponding to the P target value are being selected, C. a feeding step of a recrystallized steel sheet having a M recrystainzation, D. a cold-rolling step in order to obtain a steel sheet having a M cold-roll and E. an annealing step performed at a temperature T target during a time t target. The following terms are defined as: M target: target value of the mechanical property, M recrystallization: mechanical property after a recrystallization annealing, M cold-roll: mechanical property after cold-rolling, P target: target value of pareq, FWHM: full width at half maximum of X-ray diffraction spectrum and FWHM target: target value of the full width at half maximum of X-ray diffraction spectrum 0.1 < C < 1.2%, 13.0 ≤ Mn < 25.0%, S ≤ 0.030%, P ≤ 0.080%, N ≤ 0.1%, Si ≤ 3.0%, Nb ≤ 0.5 %, B ≤ 0.005%, Cr ≤ 1.0%, Mo ≤ 0.40%, Ni ≤ 1.0%, Cu ≤ 5.0%, Ti ≤ 0.5%, V ≤ 2.5%, Al ≤ 4.0%, 0.06 ≤ Sn ≤ 0.2, A. a calibration step wherein: at least 2 samples of said steel having undergone heat treatments between 400 and 900°C during 40 seconds to 60 minutes, corresponding to Pareq values P are prepared, Pareq being defined by: Pareq = − 0.76 ∗ log exp ∫ − Δ H RT ∗ dt with ΔH: energy of diffusion of iron in iron (equal to 300 kJ/mol), T = temperature of the cycle in Kelvin, the integration being over the heat treatment time in hour, I. said samples are submitted to X-ray diffraction so as to obtain spectrums including a main peak whose width at mid height FWHM is being measured, II. M of such samples is being measured, III. the recovery or recrystallization state of each sample is being measured, IV. the curve of M as a function of FWHM is being drawn in the domain where the samples are recovered from 0 to 100%, but not recrystallized, I. said samples are submitted to X-ray diffraction so as to obtain spectrums including a main peak whose width at mid height FWHM is being measured, II. M of such samples is being measured, III. the recovery or recrystallization state of each sample is being measured, IV. the curve of M as a function of FWHM is being drawn in the domain where the samples are recovered from 0 to 100%, but not recrystallized, B. a calculation step wherein: I. the value of FWHM target corresponding to the M target is being determined, II. the Pareq value P target of the heat treatment to perform to reach such M target is being determined and III. a time t target and a temperature T target corresponding to the P target value are being selected, I. the value of FWHM target corresponding to the M target is being determined, II. the Pareq value P target of the heat treatment to perform to reach such M target is being determined and III. a time t target and a temperature T target corresponding to the P target value are being selected, C. a feeding step of a recrystallized steel sheet having a M recrystainzation, D. a cold-rolling step in order to obtain a steel sheet having a M cold-roll and E. an annealing step performed at a temperature T target during a time t target.