materials-finishes

Vickers Hardness Testing Standards for Precision Key Blank Nickel Silver Alloys

Engineering Overview: Quality control guide on ISO 6507 micro-Vickers hardness testing (HV1) for nickel-silver key blanks, ensuring exact bitting edge retention.

Technical & Engineering Specifications

Material CuNi18Zn20 Grade 1 Commercial Nickel-Silver
Test Load HV1 (1.0 kgf Diamond Indenter)
Target Spec 175 HV1 +/- 10 HV1
Testing Standard ISO 6507-1 / ASTM E384 Micro-Vickers Hardness

Key Blank Hardness Quality Control

Key blanks that are too soft wear down quickly; keys that are too hard chip CNC cutting wheels. Quality standards mandate ISO 6507 Micro-Vickers Hardness Testing (HV1).

Hardness Benchmarks

  • Target Range: 170 to 190 HV1 for 18% nickel-silver key blanks.
  • Testing: A diamond pyramid indenter applies $1.0 ext{ kgf}$ load, verifying consistent cold-rolled hardness across blade cross-sections.

Frequently Asked Engineering & Selection Questions

Q1: What is the ideal Vickers hardness for a commercial key blank?

170 to 190 HV1, providing the perfect balance between high wear resistance and smooth CNC cutting.