How Do You Assess a Heat-Treat System with AIAG CQI-9?

If your organization performs heat treating as a special process, you know that a standard product inspection alone cannot guarantee quality. The AIAG CQI-9 Special Process: Heat Treat System Assessment (HTSA) provides a structured, auditable framework to evaluate and continuously improve your heat-treat operations. This article explains what CQI-9 is, how the assessment works, and how you can apply it effectively.

What It Is

CQI-9 is an assessment standard developed by the Automotive Industry Action Group (AIAG). It is designed to evaluate a supplier's heat-treat system—covering management, equipment, process control, and personnel—against a consistent set of requirements. The standard is widely used in automotive and other manufacturing supply chains to ensure that heat-treat processes are robust, repeatable, and compliant with customer and regulatory expectations.

The HTSA is not a one-time certification. It is a tool for ongoing system assessment, typically performed annually or as required by customers. It helps identify gaps, drive corrective actions, and standardize best practices across plants and suppliers.

How It Works: The HTSA Assessment

The CQI-9 assessment is built around a scoring system and a set of process tables. Here is the core structure:

1. Scoring System (1 to 5): Each assessment question is scored based on the level of compliance and effectiveness observed:

- 1: No system exists; noncompliance is significant.
- 2: A system exists but is ineffective or not fully implemented.
- 3: A system exists and is generally effective, with minor gaps.
- 4: A system is effective and well-implemented, with only minor opportunities for improvement.
- 5: A system is fully effective, robust, and demonstrates best-in-class practices.

1. Assessment Sections: The HTSA is divided into three main parts:

- Section A – Management Responsibility & Quality Planning: Covers leadership commitment, quality planning, and continuous improvement.
- Section B – Facility and Equipment: Evaluates the physical condition, maintenance, and calibration of heat-treat equipment.
- Section C – Process Control: Focuses on the actual heat-treat processes, including controls, monitoring, and documentation.

1. Process Tables: CQI-9 includes specific process tables (e.g., carburizing, hardening, tempering, induction hardening, etc.). Each table lists the critical process parameters, required controls, and acceptance criteria for that specific heat-treat method. The assessor must verify that the plant's procedures and records align with the applicable process table.

1. Assessment Procedure:

- Review documentation (procedures, work instructions, training records, maintenance logs).
- Conduct a walkthrough of the facility and equipment.
- Interview operators, technicians, and management.
- Verify process records and data against the process tables.
- Assign scores for each question.
- Compile findings and issue a corrective action plan for any score below 3.

A Worked Illustrative Example

Example data (illustrative only):

A heat-treat facility is assessed against the CQI-9 HTSA. In Section C (Process Control), the assessor reviews the carburizing process table. The required control is that furnace temperature must be recorded continuously and verified against the setpoint every hour.

• The plant has a temperature recorder that logs data automatically.
• However, the assessor finds that the operator only reviews the log once per shift, and there is no documented procedure for responding to a temperature deviation.
• Based on the evidence, the assessor assigns a score of 2 for this question: a system exists (the recorder), but it is not fully effective because monitoring frequency and deviation response are inadequate.

The corrective action plan requires the plant to update its work instruction to include hourly verification and a defined response protocol for temperature excursions. A follow-up assessment is scheduled within 90 days to verify closure.

Common Pitfalls

• Treating CQI-9 as a checklist, not a system. Simply scoring "yes" or "no" without evaluating effectiveness leads to superficial compliance.
• Ignoring the process tables. The process tables are the technical heart of the assessment. If your process is not mapped to the correct table, you will miss critical requirements.
• Inconsistent scoring. Ensure all assessors are trained to apply the 1–5 scale consistently. A score of 3 should mean the same thing across different plants.
• Failing to close findings. A low score is not a failure—it is an opportunity. The real failure is not implementing and verifying corrective actions.

Closing

The AIAG CQI-9 HTSA is a powerful tool to strengthen your heat-treat system and demonstrate quality capability to customers. To simplify your assessment and corrective action tracking, try our free, structured CQI-9 assessment tool at https://www.6sq.com/tools/cqi9/ and build a robust, audit-ready heat-treat system today.