The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Masao Morishita - One of the best experts on this subject based on the ideXlab platform.
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standard gibbs energy of formation of mgla determined by solution calorimetry and heat capacity measurement from near Absolute Zero kelvin
Journal of Alloys and Compounds, 2008Co-Authors: Masao Morishita, Hiroaki Yamamoto, Ai Onoue, Yasutomo MatsumotoAbstract:Abstract The standard Gibbs energy of formation, Δ f G T ° , of MgLa in the temperature range from near Absolute 0 to 525 K were determined by calorimetry. The heat capacities, C p , from 2 K to 525 K were measured by the relaxation method and DSC. Also, a thermal anomaly at 5.9 K, which appeared to be a superconductive phase transition, was found in the obtained C p values. The Δ f G T ° ( MgLa ) values were determined by combining the C p data with the standard enthalpy of formation at 298 K which was measured by the Calvet-type calorimeter using hydrochloric acid solution. From 2 to 300 K, the Δ f G T ° increases gradually, and it can be evaluated as a linear function of temperature above 300 K as follows: Δ f G T ° ( MgLa ) ( kJ mo l − 1 ) = − 39.236 − 6.9832 × 10 − 3 T + 2.1016 × 10 − 3 T log T + 1.9114 × 10 − 5 T 2 − 0.81004 T − 1 ± 7.40 ( 2 − 300 K ) , Δ f G T ° ( MgLa ) ( kJ mo l − 1 ) = − 41.100 + 9.9974 × 10 − 3 T ± 7.40 ( 300 − 525 K ) . This result is expected to be useful as basic thermodynamic data of Mg-based alloys.
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standard gibbs energy of formation of mg3la determined by solution calorimetry and heat capacity measurement from near Absolute Zero kelvin
Materials Transactions, 2007Co-Authors: Hiroaki Yamamoto, Masao Morishita, Yasutomo Matsumoto, Ai OnoueAbstract:The standard Gibbs energy of formation, Δ f G° Τ , of Mg 3 La in the temperature range from near Absolute Zero Kelvin to 525 K were determined by calorimetry. The heat capacities, Cp, from 2 K to 525 K were measured by the relaxation method and DSC. The A f G° T (Mg 3 La) values were determined by combining the Cp data with the standard enthalpy of formation at 298 K which was measured by the Calvet-type calorimeter using hydrochloric acid solution. From 2 to 350 K, the Δ f G° Τ increases gradually, and it can be evaluated as a linear function of temperature above 350 K as follows: Δ f G° Τ (Mg 3 La)/kJ mo -1 =-76.204-2.5304 x 10 -2 T+ 1.2160 x 10 -2 T log T + 1.1814 x 10 -5 T 2 - 0.80332 T -1 ± 17.0 (2-350K) Δ f G° T (Mg 3 La)/kJmol -1 =-79.652+1.9567 x 10 -2 T ± 17.0 (350-525K). This result is expected to be useful as basic thermodynamic data of Mg-based alloys.
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determination of standard entropy of formation of al11nd3 by heat capacity measurement from near Absolute Zero kelvin
Journal of Alloys and Compounds, 2007Co-Authors: Hiroaki Yamamoto, Masao Morishita, Minoru KusumotoAbstract:Abstract The thermodynamic properties of Al11Nd3 were investigated by measuring the heat capacities, Cp, from near Absolute Zero (2 K) to 300 K by the relaxation method. In the low temperature range of 2–15 K, three λ-type thermal anomalies were found. The third law entropy of Al11Nd3(Al0.786Nd0.214) at 298 K was obtained by the integration of polynomials for measured Cp. The result was as follows: S 298 ( A l 0.786 N d 0.214 ) ( J K − 1 mo l − 1 ) = − 35.12 ± 0.35. Using this value, the entropy of mixing and the standard entropy of formation at 298 K were obtained as follows: Δ mix S 298 ( A l 0.786 N d 0.214 ) ( J K − 1 mo l − 1 ) = − 2.32 ± 0.39 , Δ f S 298 ° ( A l 11 N d 3 ) ( J K − 1 mo l − 1 ) = − 32.5 ± 5.5.
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standard gibbs energy of formation of zn8la determined by solution calorimetry and measurement of heat capacity from near Absolute Zero kelvin
Materials Transactions, 2006Co-Authors: Masao Morishita, Hiroaki Yamamoto, Kohei Tsuboki, Yasutomo MatsumotoAbstract:The thermodynamic properties of Mg48Zn52 were investigated by calorimetry. The standard entropy of formation at 298 K, ΔfS298o, was determined from measuring the heat capacity, Cp, from near Absolute Zero (2 K) to 300 K by the relaxation method. The standard enthalpy of formation at 298 K, ΔfH298o, was determined by solution calorimetry in hydrochloric acid solution. The standard Gibbs energy of formation at 298 K, ΔfG298o, was determined from these data. The obtained results were as follows: ΔfH298o (Mg48Zn52)=(−1214±(300) kJ · mol−1;ΔfS298o (Mg48Zn52)=(−123±0.36) J · K−1 · mol−1; and ΔfG298o (Mg48Zn52)=(−1177±(300) kJ · mol−1. The electronic contribution to the heat capacity of Mg48Zn52 was found to be approximately equal to pure magnesium, indicating that the density of states in the vicinity of the Fermi level follows the free electron parabolic law.
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thermodynamics of the formation of magnesium zinc intermetallic compounds in the temperature range from Absolute Zero to high temperature
Acta Materialia, 2006Co-Authors: Masao Morishita, Hiroaki Yamamoto, Shinichi Shikada, Minoru Kusumoto, Yasutomo MatsumotoAbstract:Abstract The standard Gibbs energies of formation ( Δ f G T ∘ ) of Mg–Zn binary compounds in the temperature range from near Absolute Zero to high temperature were determined by calorimetry for the first time. Their heat capacities (Cp) from near Absolute Zero (2 K) to high temperature were measured by the relaxation method and differential scanning calorimetry. Their Δ f G T ∘ values were determined by combining the Cp data with the standard enthalpies of formation at 298 K ( Δ f H 298 ∘ ) which were previously determined by solution calorimetry in hydrochloric acid solution. From near Absolute Zero to 300 K, the Δ f G T ∘ values increase monotonically, and then above 300 K they can be evaluated as a linear function of temperature as follows (in kJ mol−1): Δ f G T ∘ ( Mg 48 Zn 52 ) = - 12.15 × 10 2 + 0.135 T ( ± 300 ) ( 300 – 530 K ) ; Δ f G T ∘ ( α - Mg 2 Zn 3 ) = - 69.95 + 1.15 × 10 - 2 T ( ± 20 ) ( 300 – 557.14 K ) ; Δ f G T ∘ ( β - Mg 2 Zn 3 ) = - 68.00 + 8.00 × 10 − 3 T ( ± 20 ) ( 557.14 – 640 K ) ; Δ f G T ∘ ( MgZn 2 ) = - 41.61 + 6.66 × 10 − 3 T ( ± 9 ) ( 300 – 680 K ) ; Δ f G T ∘ ( Mg 2 Zn 11 ) = - 118.17 + 2.67 × 10 − 2 T ( ± 39 ) ( 300 – 530 K ) . The results obtained are expected to be useful as basic thermodynamic data for Mg-based alloys.
Yasutomo Matsumoto - One of the best experts on this subject based on the ideXlab platform.
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standard gibbs energy of formation of mgla determined by solution calorimetry and heat capacity measurement from near Absolute Zero kelvin
Journal of Alloys and Compounds, 2008Co-Authors: Masao Morishita, Hiroaki Yamamoto, Ai Onoue, Yasutomo MatsumotoAbstract:Abstract The standard Gibbs energy of formation, Δ f G T ° , of MgLa in the temperature range from near Absolute 0 to 525 K were determined by calorimetry. The heat capacities, C p , from 2 K to 525 K were measured by the relaxation method and DSC. Also, a thermal anomaly at 5.9 K, which appeared to be a superconductive phase transition, was found in the obtained C p values. The Δ f G T ° ( MgLa ) values were determined by combining the C p data with the standard enthalpy of formation at 298 K which was measured by the Calvet-type calorimeter using hydrochloric acid solution. From 2 to 300 K, the Δ f G T ° increases gradually, and it can be evaluated as a linear function of temperature above 300 K as follows: Δ f G T ° ( MgLa ) ( kJ mo l − 1 ) = − 39.236 − 6.9832 × 10 − 3 T + 2.1016 × 10 − 3 T log T + 1.9114 × 10 − 5 T 2 − 0.81004 T − 1 ± 7.40 ( 2 − 300 K ) , Δ f G T ° ( MgLa ) ( kJ mo l − 1 ) = − 41.100 + 9.9974 × 10 − 3 T ± 7.40 ( 300 − 525 K ) . This result is expected to be useful as basic thermodynamic data of Mg-based alloys.
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standard gibbs energy of formation of mg3la determined by solution calorimetry and heat capacity measurement from near Absolute Zero kelvin
Materials Transactions, 2007Co-Authors: Hiroaki Yamamoto, Masao Morishita, Yasutomo Matsumoto, Ai OnoueAbstract:The standard Gibbs energy of formation, Δ f G° Τ , of Mg 3 La in the temperature range from near Absolute Zero Kelvin to 525 K were determined by calorimetry. The heat capacities, Cp, from 2 K to 525 K were measured by the relaxation method and DSC. The A f G° T (Mg 3 La) values were determined by combining the Cp data with the standard enthalpy of formation at 298 K which was measured by the Calvet-type calorimeter using hydrochloric acid solution. From 2 to 350 K, the Δ f G° Τ increases gradually, and it can be evaluated as a linear function of temperature above 350 K as follows: Δ f G° Τ (Mg 3 La)/kJ mo -1 =-76.204-2.5304 x 10 -2 T+ 1.2160 x 10 -2 T log T + 1.1814 x 10 -5 T 2 - 0.80332 T -1 ± 17.0 (2-350K) Δ f G° T (Mg 3 La)/kJmol -1 =-79.652+1.9567 x 10 -2 T ± 17.0 (350-525K). This result is expected to be useful as basic thermodynamic data of Mg-based alloys.
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standard gibbs energy of formation of zn8la determined by solution calorimetry and measurement of heat capacity from near Absolute Zero kelvin
Materials Transactions, 2006Co-Authors: Masao Morishita, Hiroaki Yamamoto, Kohei Tsuboki, Yasutomo MatsumotoAbstract:The thermodynamic properties of Mg48Zn52 were investigated by calorimetry. The standard entropy of formation at 298 K, ΔfS298o, was determined from measuring the heat capacity, Cp, from near Absolute Zero (2 K) to 300 K by the relaxation method. The standard enthalpy of formation at 298 K, ΔfH298o, was determined by solution calorimetry in hydrochloric acid solution. The standard Gibbs energy of formation at 298 K, ΔfG298o, was determined from these data. The obtained results were as follows: ΔfH298o (Mg48Zn52)=(−1214±(300) kJ · mol−1;ΔfS298o (Mg48Zn52)=(−123±0.36) J · K−1 · mol−1; and ΔfG298o (Mg48Zn52)=(−1177±(300) kJ · mol−1. The electronic contribution to the heat capacity of Mg48Zn52 was found to be approximately equal to pure magnesium, indicating that the density of states in the vicinity of the Fermi level follows the free electron parabolic law.
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thermodynamics of the formation of magnesium zinc intermetallic compounds in the temperature range from Absolute Zero to high temperature
Acta Materialia, 2006Co-Authors: Masao Morishita, Hiroaki Yamamoto, Shinichi Shikada, Minoru Kusumoto, Yasutomo MatsumotoAbstract:Abstract The standard Gibbs energies of formation ( Δ f G T ∘ ) of Mg–Zn binary compounds in the temperature range from near Absolute Zero to high temperature were determined by calorimetry for the first time. Their heat capacities (Cp) from near Absolute Zero (2 K) to high temperature were measured by the relaxation method and differential scanning calorimetry. Their Δ f G T ∘ values were determined by combining the Cp data with the standard enthalpies of formation at 298 K ( Δ f H 298 ∘ ) which were previously determined by solution calorimetry in hydrochloric acid solution. From near Absolute Zero to 300 K, the Δ f G T ∘ values increase monotonically, and then above 300 K they can be evaluated as a linear function of temperature as follows (in kJ mol−1): Δ f G T ∘ ( Mg 48 Zn 52 ) = - 12.15 × 10 2 + 0.135 T ( ± 300 ) ( 300 – 530 K ) ; Δ f G T ∘ ( α - Mg 2 Zn 3 ) = - 69.95 + 1.15 × 10 - 2 T ( ± 20 ) ( 300 – 557.14 K ) ; Δ f G T ∘ ( β - Mg 2 Zn 3 ) = - 68.00 + 8.00 × 10 − 3 T ( ± 20 ) ( 557.14 – 640 K ) ; Δ f G T ∘ ( MgZn 2 ) = - 41.61 + 6.66 × 10 − 3 T ( ± 9 ) ( 300 – 680 K ) ; Δ f G T ∘ ( Mg 2 Zn 11 ) = - 118.17 + 2.67 × 10 − 2 T ( ± 39 ) ( 300 – 530 K ) . The results obtained are expected to be useful as basic thermodynamic data for Mg-based alloys.
Hiroaki Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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standard gibbs energy of formation of mgla determined by solution calorimetry and heat capacity measurement from near Absolute Zero kelvin
Journal of Alloys and Compounds, 2008Co-Authors: Masao Morishita, Hiroaki Yamamoto, Ai Onoue, Yasutomo MatsumotoAbstract:Abstract The standard Gibbs energy of formation, Δ f G T ° , of MgLa in the temperature range from near Absolute 0 to 525 K were determined by calorimetry. The heat capacities, C p , from 2 K to 525 K were measured by the relaxation method and DSC. Also, a thermal anomaly at 5.9 K, which appeared to be a superconductive phase transition, was found in the obtained C p values. The Δ f G T ° ( MgLa ) values were determined by combining the C p data with the standard enthalpy of formation at 298 K which was measured by the Calvet-type calorimeter using hydrochloric acid solution. From 2 to 300 K, the Δ f G T ° increases gradually, and it can be evaluated as a linear function of temperature above 300 K as follows: Δ f G T ° ( MgLa ) ( kJ mo l − 1 ) = − 39.236 − 6.9832 × 10 − 3 T + 2.1016 × 10 − 3 T log T + 1.9114 × 10 − 5 T 2 − 0.81004 T − 1 ± 7.40 ( 2 − 300 K ) , Δ f G T ° ( MgLa ) ( kJ mo l − 1 ) = − 41.100 + 9.9974 × 10 − 3 T ± 7.40 ( 300 − 525 K ) . This result is expected to be useful as basic thermodynamic data of Mg-based alloys.
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standard gibbs energy of formation of mg3la determined by solution calorimetry and heat capacity measurement from near Absolute Zero kelvin
Materials Transactions, 2007Co-Authors: Hiroaki Yamamoto, Masao Morishita, Yasutomo Matsumoto, Ai OnoueAbstract:The standard Gibbs energy of formation, Δ f G° Τ , of Mg 3 La in the temperature range from near Absolute Zero Kelvin to 525 K were determined by calorimetry. The heat capacities, Cp, from 2 K to 525 K were measured by the relaxation method and DSC. The A f G° T (Mg 3 La) values were determined by combining the Cp data with the standard enthalpy of formation at 298 K which was measured by the Calvet-type calorimeter using hydrochloric acid solution. From 2 to 350 K, the Δ f G° Τ increases gradually, and it can be evaluated as a linear function of temperature above 350 K as follows: Δ f G° Τ (Mg 3 La)/kJ mo -1 =-76.204-2.5304 x 10 -2 T+ 1.2160 x 10 -2 T log T + 1.1814 x 10 -5 T 2 - 0.80332 T -1 ± 17.0 (2-350K) Δ f G° T (Mg 3 La)/kJmol -1 =-79.652+1.9567 x 10 -2 T ± 17.0 (350-525K). This result is expected to be useful as basic thermodynamic data of Mg-based alloys.
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determination of standard entropy of formation of al11nd3 by heat capacity measurement from near Absolute Zero kelvin
Journal of Alloys and Compounds, 2007Co-Authors: Hiroaki Yamamoto, Masao Morishita, Minoru KusumotoAbstract:Abstract The thermodynamic properties of Al11Nd3 were investigated by measuring the heat capacities, Cp, from near Absolute Zero (2 K) to 300 K by the relaxation method. In the low temperature range of 2–15 K, three λ-type thermal anomalies were found. The third law entropy of Al11Nd3(Al0.786Nd0.214) at 298 K was obtained by the integration of polynomials for measured Cp. The result was as follows: S 298 ( A l 0.786 N d 0.214 ) ( J K − 1 mo l − 1 ) = − 35.12 ± 0.35. Using this value, the entropy of mixing and the standard entropy of formation at 298 K were obtained as follows: Δ mix S 298 ( A l 0.786 N d 0.214 ) ( J K − 1 mo l − 1 ) = − 2.32 ± 0.39 , Δ f S 298 ° ( A l 11 N d 3 ) ( J K − 1 mo l − 1 ) = − 32.5 ± 5.5.
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standard gibbs energy of formation of zn8la determined by solution calorimetry and measurement of heat capacity from near Absolute Zero kelvin
Materials Transactions, 2006Co-Authors: Masao Morishita, Hiroaki Yamamoto, Kohei Tsuboki, Yasutomo MatsumotoAbstract:The thermodynamic properties of Mg48Zn52 were investigated by calorimetry. The standard entropy of formation at 298 K, ΔfS298o, was determined from measuring the heat capacity, Cp, from near Absolute Zero (2 K) to 300 K by the relaxation method. The standard enthalpy of formation at 298 K, ΔfH298o, was determined by solution calorimetry in hydrochloric acid solution. The standard Gibbs energy of formation at 298 K, ΔfG298o, was determined from these data. The obtained results were as follows: ΔfH298o (Mg48Zn52)=(−1214±(300) kJ · mol−1;ΔfS298o (Mg48Zn52)=(−123±0.36) J · K−1 · mol−1; and ΔfG298o (Mg48Zn52)=(−1177±(300) kJ · mol−1. The electronic contribution to the heat capacity of Mg48Zn52 was found to be approximately equal to pure magnesium, indicating that the density of states in the vicinity of the Fermi level follows the free electron parabolic law.
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thermodynamics of the formation of magnesium zinc intermetallic compounds in the temperature range from Absolute Zero to high temperature
Acta Materialia, 2006Co-Authors: Masao Morishita, Hiroaki Yamamoto, Shinichi Shikada, Minoru Kusumoto, Yasutomo MatsumotoAbstract:Abstract The standard Gibbs energies of formation ( Δ f G T ∘ ) of Mg–Zn binary compounds in the temperature range from near Absolute Zero to high temperature were determined by calorimetry for the first time. Their heat capacities (Cp) from near Absolute Zero (2 K) to high temperature were measured by the relaxation method and differential scanning calorimetry. Their Δ f G T ∘ values were determined by combining the Cp data with the standard enthalpies of formation at 298 K ( Δ f H 298 ∘ ) which were previously determined by solution calorimetry in hydrochloric acid solution. From near Absolute Zero to 300 K, the Δ f G T ∘ values increase monotonically, and then above 300 K they can be evaluated as a linear function of temperature as follows (in kJ mol−1): Δ f G T ∘ ( Mg 48 Zn 52 ) = - 12.15 × 10 2 + 0.135 T ( ± 300 ) ( 300 – 530 K ) ; Δ f G T ∘ ( α - Mg 2 Zn 3 ) = - 69.95 + 1.15 × 10 - 2 T ( ± 20 ) ( 300 – 557.14 K ) ; Δ f G T ∘ ( β - Mg 2 Zn 3 ) = - 68.00 + 8.00 × 10 − 3 T ( ± 20 ) ( 557.14 – 640 K ) ; Δ f G T ∘ ( MgZn 2 ) = - 41.61 + 6.66 × 10 − 3 T ( ± 9 ) ( 300 – 680 K ) ; Δ f G T ∘ ( Mg 2 Zn 11 ) = - 118.17 + 2.67 × 10 − 2 T ( ± 39 ) ( 300 – 530 K ) . The results obtained are expected to be useful as basic thermodynamic data for Mg-based alloys.
Minoru Kusumoto - One of the best experts on this subject based on the ideXlab platform.
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determination of standard entropy of formation of al11nd3 by heat capacity measurement from near Absolute Zero kelvin
Journal of Alloys and Compounds, 2007Co-Authors: Hiroaki Yamamoto, Masao Morishita, Minoru KusumotoAbstract:Abstract The thermodynamic properties of Al11Nd3 were investigated by measuring the heat capacities, Cp, from near Absolute Zero (2 K) to 300 K by the relaxation method. In the low temperature range of 2–15 K, three λ-type thermal anomalies were found. The third law entropy of Al11Nd3(Al0.786Nd0.214) at 298 K was obtained by the integration of polynomials for measured Cp. The result was as follows: S 298 ( A l 0.786 N d 0.214 ) ( J K − 1 mo l − 1 ) = − 35.12 ± 0.35. Using this value, the entropy of mixing and the standard entropy of formation at 298 K were obtained as follows: Δ mix S 298 ( A l 0.786 N d 0.214 ) ( J K − 1 mo l − 1 ) = − 2.32 ± 0.39 , Δ f S 298 ° ( A l 11 N d 3 ) ( J K − 1 mo l − 1 ) = − 32.5 ± 5.5.
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thermodynamics of the formation of magnesium zinc intermetallic compounds in the temperature range from Absolute Zero to high temperature
Acta Materialia, 2006Co-Authors: Masao Morishita, Hiroaki Yamamoto, Shinichi Shikada, Minoru Kusumoto, Yasutomo MatsumotoAbstract:Abstract The standard Gibbs energies of formation ( Δ f G T ∘ ) of Mg–Zn binary compounds in the temperature range from near Absolute Zero to high temperature were determined by calorimetry for the first time. Their heat capacities (Cp) from near Absolute Zero (2 K) to high temperature were measured by the relaxation method and differential scanning calorimetry. Their Δ f G T ∘ values were determined by combining the Cp data with the standard enthalpies of formation at 298 K ( Δ f H 298 ∘ ) which were previously determined by solution calorimetry in hydrochloric acid solution. From near Absolute Zero to 300 K, the Δ f G T ∘ values increase monotonically, and then above 300 K they can be evaluated as a linear function of temperature as follows (in kJ mol−1): Δ f G T ∘ ( Mg 48 Zn 52 ) = - 12.15 × 10 2 + 0.135 T ( ± 300 ) ( 300 – 530 K ) ; Δ f G T ∘ ( α - Mg 2 Zn 3 ) = - 69.95 + 1.15 × 10 - 2 T ( ± 20 ) ( 300 – 557.14 K ) ; Δ f G T ∘ ( β - Mg 2 Zn 3 ) = - 68.00 + 8.00 × 10 − 3 T ( ± 20 ) ( 557.14 – 640 K ) ; Δ f G T ∘ ( MgZn 2 ) = - 41.61 + 6.66 × 10 − 3 T ( ± 9 ) ( 300 – 680 K ) ; Δ f G T ∘ ( Mg 2 Zn 11 ) = - 118.17 + 2.67 × 10 − 2 T ( ± 39 ) ( 300 – 530 K ) . The results obtained are expected to be useful as basic thermodynamic data for Mg-based alloys.
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standard gibbs energy of formation of mg48zn52 determined by solution calorimetry and measurement of heat capacity from near Absolute Zero kelvin
Metallurgical and Materials Transactions B-process Metallurgy and Materials Processing Science, 2004Co-Authors: Masao Morishita, Koichiro Koyama, S Shikata, Minoru KusumotoAbstract:The thermodynamic properties of Mg48Zn52 were investigated by calorimetry. The standard entropy of formation at 298 K, Δf S 298 o , was determined from measuring the heat capacity, C p , from near Absolute Zero (2 K) to 300 K by the relaxation method. The standard enthalpy of formation at 298 K, Δf H 298 o , was determined by solution calorimetry in hydrochloric acid solution. The standard Gibbs energy of formation at 298 K, Δf G 298 o , was determined from these data. The obtained results were as follows: Δf H 298 o (Mg48Zn52)=(−1214±(300) kJ · mol−1;ΔfS 298 o (Mg48Zn52)=(−123±0.36) J · K−1 · mol−1; and Δf G 298 o (Mg48Zn52)=(−1177±(300) kJ · mol−1. The electronic contribution to the heat capacity of Mg48Zn52 was found to be approximately equal to pure magnesium, indicating that the density of states in the vicinity of the Fermi level follows the free electron parabolic law.
Dingguo Sha - One of the best experts on this subject based on the ideXlab platform.
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laser differential confocal radius measurement
Optics Express, 2010Co-Authors: Weiqian Zhao, Lirong Qiu, Ruoduan Sun, Dingguo ShaAbstract:A new laser differential confocal radius measurement (DCRM) is proposed for high precision measurement of radius. Based on the property of an axial intensity curve that the Absolute Zero precisely corresponds to the focus of the objective in a differential confocal system (DCS), DCRM uses the Zero point of the DCS axial intensity curve to precisely identify the cat's-eye and confocal positions of the test lens, and measures the accurate distance between the two positions to achieve the high-precision measurement of radius of curvature (ROC). In comparison with the existing measurement methods, DCRM proposed has a high measurement precision, a strong environmental anti-interference capability and a low cost. The theoretical analyses and preliminary experimental results indicate that DCRM has a relative measurement error of better than 5ppm.
