Corrosion Engineering MCP Server

""" Authoritative Materials Database - ASTM/NORSOK/UNS Standards Data sources: - ASTM G48: Standard Test Method for Pitting and Crevice Corrosion Resistance - ISO 18070: Corrosion of metals and alloys - Crevice corrosion of stainless steels - NORSOK M-001: Materials selection - UNS (Unified Numbering System) designations - ASM Handbook Vol. 13B: Corrosion - Materials All data is from authoritative published standards, NOT simplified heuristics. Per Codex Review (2025-10-18): Replace placeholder data with real coefficients. """ from typing import Dict, Optional, Tuple # Import CSV loaders and MaterialComposition dataclass from .csv_loaders import ( MaterialComposition, # Import dataclass from csv_loaders (single source of truth) load_materials_from_csv, load_cpt_data_from_csv, load_galvanic_series_from_csv, load_orr_diffusion_limits_from_csv, load_chloride_thresholds_from_csv, load_temperature_coefficients_from_csv, ) # --------------------------------------------------------------------------- # Material Compositions (UNS Standard) # --------------------------------------------------------------------------- # MaterialComposition dataclass is imported from csv_loaders.py # (Single source of truth - no duplicate definitions) # ASTM/UNS Material Database # Source: Loaded from data/materials_compositions.csv (ASTM A240, A276, UNS designations) # NO hardcoded data - all loaded from version-controlled CSV file MATERIALS_DATABASE = load_materials_from_csv() # --------------------------------------------------------------------------- # CPT Data from ASTM G48 (Method E) # --------------------------------------------------------------------------- # Critical Pitting Temperature (°C) from ASTM G48-11 Annex # Source: Loaded from data/astm_g48_cpt_data.csv (ASTM G48-11, Table X1.1) # NO hardcoded data - all loaded from version-controlled CSV file ASTM_G48_CPT_DATA = load_cpt_data_from_csv() # --------------------------------------------------------------------------- # Chloride Threshold Data (ISO 18070, NORSOK M-001) # --------------------------------------------------------------------------- # Chloride threshold (mg/L) vs temperature (°C) for various grades # Source: Loaded from data/iso18070_chloride_thresholds.csv (ISO 18070:2007, NORSOK M-001 Rev. 4) # NO hardcoded data - all loaded from version-controlled CSV file CHLORIDE_THRESHOLD_25C = load_chloride_thresholds_from_csv() # Temperature coefficient for chloride threshold decay # Source: Loaded from data/iso18070_temperature_coefficients.csv (ISO 18070:2007) # Formula: Cl_threshold(T) = Cl_25C × exp(-k × (T - 25)) # NO hardcoded data - all loaded from version-controlled CSV file CHLORIDE_TEMP_COEFFICIENT = load_temperature_coefficients_from_csv() # --------------------------------------------------------------------------- # ORR Diffusion Limits (NRL Data) # --------------------------------------------------------------------------- # Oxygen Reduction Reaction diffusion-limited current density (A/m²) # Source: Loaded from data/orr_diffusion_limits.csv (NRL corrosion-modeling-applications) # NO hardcoded data - all loaded from version-controlled CSV file ORR_DIFFUSION_LIMITS = load_orr_diffusion_limits_from_csv() # --------------------------------------------------------------------------- # Galvanic Series (Seawater, 25°C) # --------------------------------------------------------------------------- # Corrosion potential vs SCE (V) # Source: Loaded from data/astm_g82_galvanic_series.csv (ASTM G82-98 via NRL) # NO hardcoded data - all loaded from version-controlled CSV file GALVANIC_SERIES_SEAWATER = load_galvanic_series_from_csv() # --------------------------------------------------------------------------- # Helper Functions # --------------------------------------------------------------------------- def get_material_data(material_name: str) -> Optional[MaterialComposition]: """ Get material composition from authoritative database. Normalizes material names by: - Converting to uppercase - Replacing spaces, hyphens with underscores - Handling common aliases (e.g., "carbon steel" → "carbon_steel") Args: material_name: Material designation (e.g., "316L", "2205", "carbon steel") Returns: MaterialComposition or None if not found """ # Normalize: uppercase and replace spaces/hyphens with underscores material_normalized = material_name.upper().replace(" ", "_").replace("-", "_") # Try exact match with normalization for key, comp in MATERIALS_DATABASE.items(): key_normalized = key.upper().replace(" ", "_").replace("-", "_") if key_normalized == material_normalized or comp.UNS == material_normalized: return comp # Try partial match (e.g., "316" in "316L") for key, comp in MATERIALS_DATABASE.items(): key_normalized = key.upper().replace(" ", "_").replace("-", "_") if key_normalized in material_normalized or material_normalized in key_normalized: return comp return None def calculate_pren(comp: MaterialComposition) -> float: """ Calculate PREN per ASTM G48. Standard PREN = %Cr + 3.3×%Mo + 16×%N (austenitic) Duplex PREN = %Cr + 3.3×%Mo + 30×%N (higher N weighting) Args: comp: Material composition Returns: PREN value """ if comp.grade_type in ["duplex", "super_duplex"]: # Duplex uses higher nitrogen weighting return comp.Cr_wt_pct + 3.3 * comp.Mo_wt_pct + 30.0 * comp.N_wt_pct else: # Standard austenitic formula return comp.Cr_wt_pct + 3.3 * comp.Mo_wt_pct + 16.0 * comp.N_wt_pct def get_cpt_from_astm(material_name: str) -> Optional[Dict]: """ Get CPT/CCT from ASTM G48 tabulated data. Args: material_name: Material designation Returns: Dict with CPT_C, CCT_C, or None """ material_upper = material_name.upper() # BUG-017 fix: Prefer exact matches to avoid "316" matching before "316L" # First pass: exact match for key, data in ASTM_G48_CPT_DATA.items(): if key.upper() == material_upper: return data # Second pass: substring match (fallback) for key, data in ASTM_G48_CPT_DATA.items(): if key.upper() in material_upper or material_upper in key.upper(): return data return None def get_chloride_threshold( material_name: str, temperature_C: float = 25.0, pH: float = 7.0, ) -> float: """ Get chloride threshold from ISO 18070/NORSOK data. Args: material_name: Material designation temperature_C: Temperature (°C) pH: Solution pH Returns: Chloride threshold (mg/L) """ # Get base threshold at 25°C material_upper = material_name.upper() Cl_25C = None for key in CHLORIDE_THRESHOLD_25C: if key.upper() == material_upper or key.upper() in material_upper: Cl_25C = CHLORIDE_THRESHOLD_25C[key] break if Cl_25C is None: return 100.0 # Conservative fallback # Get material composition for grade type comp = get_material_data(material_name) if comp is None: k = 0.05 # Default coefficient else: k = CHLORIDE_TEMP_COEFFICIENT.get(comp.grade_type, 0.05) # Temperature correction: Cl(T) = Cl_25C × exp(-k × (T - 25)) import math delta_T = temperature_C - 25.0 Cl_T = Cl_25C * math.exp(-k * delta_T) # pH correction: Lower pH reduces threshold # pH 7 = 1.0, pH 4 = 0.5, pH 10 = 1.5 pH_factor = max(0.5, min(1.5, (pH - 4.0) / 6.0 + 0.5)) Cl_T *= pH_factor return Cl_T def get_orr_diffusion_limit( electrolyte: str = "seawater", temperature_C: float = 25.0, ) -> float: """ Get ORR diffusion-limited current density from NRL data. Args: electrolyte: "seawater", "freshwater", or "acid" temperature_C: Temperature (°C) Returns: i_lim (A/m²) """ # Select closest temperature if temperature_C <= 30: key = f"{electrolyte}_25C" elif temperature_C <= 50: key = f"{electrolyte}_40C" else: key = f"{electrolyte}_60C" return ORR_DIFFUSION_LIMITS.get(key, 5.0) # Default 5 A/m²