Datalloy 2 is a proprietary electro-slag remelted (ESR) chromium-manganese-nitrogen austenitic stainless alloy, developed and trademarked by ATI (formerly Carpenter Technology / Latrobe Specialty Steel) for non-magnetic drill-string components in directional drilling: MWD and LWD tool housings, stabilizers, drill collars, and compressive service drill pipe used in the oil and gas industry. Rather than relying on nickel and molybdenum alone, its strength comes from a nitrogen-alloyed austenitic matrix combined with controlled hot forging and heavy cold working — Datalloy 2 cannot be hardened by conventional heat treatment, and mill certifications specify a minimum 0.2% yield strength, with a "High Strength" condition guaranteeing 140 ksi minimum yield.

The alloy was engineered specifically to resist the two corrosion modes that are hardest on drill collars: localized pitting in oxidized or stagnant drilling mud, and galvanic attack where the collar contacts dissimilar metals (including direct coupling to copper). It also maintains a maximum magnetic permeability of 1.005, which is why it is specified anywhere a true non-magnetic zone is required near directional-survey instrumentation. Because Datalloy 2 is a trademarked ESR product rather than a designation registered under AISI, DIN, or ASTM, there is no widely published cross-reference to an equivalent national standard grade — specification is done directly against the ATI Datalloy 2 technical data sheet and API 7-1.

Datalloy 2 is a proprietary ESR alloy without a registered UNS, AISI, DIN, or Wnr. cross-designation in publicly available references. Do not substitute standard Cr-Mn stainless grades without verifying pitting/galvanic corrosion performance against the ATI data sheet.

Nominal composition per ATI Datalloy 2 ESR technical data sheet. Producer's published compositional window allows Mn 10-20%, Cr 13.5-18.0%, Ni 1.0-4.0%, Mo 1.5-3.5%, N 0.2-0.4% depending on product form.

Datalloy 2 machines like a high-alloy austenitic stainless rather than a martensitic PH grade: it is ductile, gummy in chip formation, and work-hardens aggressively if the tool is allowed to rub or dwell. ATI's own comparison places its machinability close to other high-strength non-magnetic drill collar alloys — meaningfully harder to cut than 304/316 due to the combined 15% Mn / 15% Cr / 2% Mo alloy load and the strain-hardened condition it is normally supplied in. Because the material cannot be softened by heat treatment, the hardness and strength encountered at the tool tip is essentially whatever the mill delivered, so cutting data should be treated as a starting point and adjusted downward on higher-strength (140 ksi+) certified stock.

Positive, sharp geometries with adequate feed are essential — light, hesitant cuts glaze the surface and accelerate notch wear at the depth-of-cut line. Continuous, well-directed coolant is important both to control heat (low thermal conductivity concentrates it at the edge) and to help break the long, stringy chips this alloy tends to produce. Interrupted or resumed cuts should be avoided wherever possible since re-entering a work-hardened skin is one of the fastest ways to chip a PVD edge on this material.

Turning

Parting / Grooving

Milling