estimated gamma prime vol% The estimated gamma prime volume fraction from the solubility-based model, in percent. is approximate Whether the quantity value is approximate. Processing Method The manufacturing or processing route applied to an alloy (e.g., wrought, cast). Gamma Prime Phase The ordered L1_2 gamma prime precipitate phase (Ni3Al-type). TCP Risk Moderate Alloy variant with moderate TCP phase formation risk: Md_avg between 0.940 and 0.960. Property Set A collection of measurements for a specific mechanical property type. Solid Solution Strengthened Alloy An alloy classified as solid-solution strengthened: gamma-prime former content (Al+Ti+Ta+0.35*Nb) below 2.0 wt%. maximum value (inclusive) The maximum bound of a quantity range. processing method (literal) The processing route as a string literal (denormalised convenience property). precipitation hardening coefficient The precipitation hardening coefficient proportional to f^0.5 x (Al+Ti). unit symbol The symbol of the unit of measurement (e.g., MPa, GPa, %). Nickel-Based Superalloy A nickel-based superalloy material. oxidation resistance An oxidation resistance metric derived from Cr and Al content. AlloyGraph Ontology Ontology for Ni-based superalloys with composition, processing, mechanical properties, computed metallurgical features, and OWL DL classification axioms for alloy type and TCP risk. 1.2.0 AlloyGraph Project 2026-03-18 qualifier A qualifier for the quantity (e.g., minimum, typical). has form Links a variant to its physical product form. heat treatment condition The heat treatment condition under which the measurement was taken. Chemical Element A chemical element present in an alloy composition. Material Base class for all materials. Mechanical Property Base class for mechanical properties of materials. Md gamma (matrix) The Morinaga d-electron parameter computed from the estimated gamma matrix composition. SSS total wt% Total weight percent of solid-solution strengthening elements (Mo+W+Nb+Ta+Re). Composition Entry A single element entry in a composition, mapping an element to its weight-percent quantity via an n-ary relation pattern. has unit Links a quantity to its unit of measurement. 0.96 has property set Links a variant to a set of measurements for a property type. Al/Ti ratio (wt%) The aluminium-to-titanium weight percent ratio. Measurement A single measurement data point recording a property value at a specific test condition. has processing method Links a variant to its manufacturing processing method. 1 is balance remainder Whether the composition entry represents the balance element (typically Ni). Al/Ti ratio (at%) The aluminium-to-titanium atomic percent ratio. lattice mismatch % The lattice mismatch between gamma and gamma prime phases, in percent. 0.94 temperature category A categorical label for the test temperature range (e.g., room temperature, elevated). has test temperature Links a measurement to the temperature at which it was performed. Reduction of Area The reduction of area at fracture, measured in percent. measured density The experimentally measured density in g/cm3. trade designation The commercial trade name of a superalloy. has mass fraction Links a composition entry to its weight-percent quantity. TCP risk classification The TCP phase formation risk level (Low, Moderate, Elevated, or Critical). Quantity A numeric quantity with an optional unit, range, and qualifier. Gamma Prime Precipitation Hardened Alloy An alloy classified as gamma-prime precipitation hardened: gamma-prime former content (Al+Ti+Ta+0.35*Nb) at or above 2.0 wt%. 1 85.0 Yield Strength The 0.2% offset yield strength, measured in MPa. TCP Risk Critical Alloy variant with critical TCP phase formation risk: Md_avg at or above 0.985. has phase Links a variant to a phase present in its microstructure. 0.985 typical heat treatment Description of the typical heat treatment applied. Density The material density, measured in g/cm3. is component of Inverse of hasComponent; links an element entry back to its composition. has measurement Links a property set to an individual measurement data point. VEC average The valence electron concentration averaged over the alloy composition. Variant A specific variant of an alloy defined by its processing route and product form. has variant Links a superalloy to one of its processing/form variants. TCP Risk Elevated Alloy variant with elevated TCP phase formation risk: Md_avg between 0.960 and 0.985. is variant of Inverse of hasVariant; links a variant back to its parent superalloy. product form (literal) The product form as a string literal. Cr/Co ratio The chromium-to-cobalt weight percent ratio. TCP Risk Low Alloy variant with low TCP phase formation risk: Md_avg below 0.940. TCP Phase A topologically close-packed phase detrimental to mechanical properties (e.g., sigma, mu, Laves). Gamma Phase The face-centred cubic (FCC) gamma matrix phase. gamma prime composition (JSON) The estimated gamma prime composition in atomic percent, serialised as a JSON string. has heat treatment Links a variant to its heat treatment. GP formers at% Total atomic percent of gamma-prime forming elements (Al+Ti+Ta+Nb). Cr x Al interaction The Cr-Al interaction term (product of weight percentages). stress The applied stress for creep rupture tests, in MPa. 1 0.0 Composition The chemical composition of an alloy expressed as a set of element entries. 7.0 Product Form The physical product form of an alloy variant (e.g., bar, sheet, forged). raw string The original string representation of the quantity as parsed from the source data. Md average (bulk) The Morinaga d-electron parameter averaged over the bulk alloy composition. Elongation The elongation at break, measured in percent. has component Links a composition to one of its element entries. GP formers wt% Total weight percent of gamma-prime forming elements (Al+Ti+Ta+Nb). atomic composition (JSON) The full alloy composition in atomic percent, serialised as a JSON string. Cr/Ni ratio The chromium-to-nickel weight percent ratio. calculated density The alloy density calculated from the inverse rule of mixtures, in g/cm3. Unit A unit of measurement. 0.985 Phase A thermodynamic phase in the alloy microstructure. 0.94 numeric value The numeric value of a quantity. 1.05 measures property Links a property set to the type of mechanical property it measures. minimum value (inclusive) The minimum bound of a quantity range. -2.0 2.0 0.96 has quantity Links a measurement to its numeric quantity value. Heat Treatment A heat treatment applied to an alloy variant. UNS number The Unified Numbering System identifier for the alloy. Ultimate Tensile Strength The ultimate tensile strength, measured in MPa. Al x Ti interaction The Al-Ti interaction term (product of atomic percentages). 0.7 Creep Rupture The creep rupture life at a given stress and temperature. has composition Links a variant to its chemical composition. alloy family The alloy family classification. 2.0 other constituents Description of other minor or trace constituents in the composition. 10.0 Hardness A hardness measurement (e.g., Vickers, Rockwell). gamma composition (JSON) The estimated gamma matrix composition in atomic percent, serialised as a JSON string. measured gamma prime vol% The experimentally measured gamma prime volume fraction in percent. SSS coefficient The solid solution strengthening coefficient computed via the Labusch-Nabarro model. element Links a composition entry to the chemical element it represents. 1 0.985 2.0 Elastic Modulus The elastic modulus (Young's modulus), measured in GPa. Mo/W ratio The molybdenum-to-tungsten weight percent ratio. 85.0 creep resistance parameter A creep resistance parameter weighted by Re, Ru, and W content. -2.0 0.7 refractory total wt% Total weight percent of refractory elements (Mo+W+Ta+Re+Nb+Hf). 1.05 life hours The creep rupture life in hours. 2.0 0.94 0.96 2.0 0.985 0.94 7.0 0.96 2.0 10.0 0.0