Block D – Heat Treatment

Context

Tool and die makers must have knowledge of heat treating required to change the properties of materials. The processes are used to harden, improve machineability and reduce internal stress. Tool and die makers must be able to perform simple heat treating operations such as torch hardening, quenching and tempering of steels.

Tool and die makers must be able to test heat treated materials to determine specific characteristics. This is imperative to verify the condition of the material.

Trends

New surface treatments driven by increased durability requirements are now available on the market. These treatments such as hard chrome and titanium nitride coatings enhance the surface performance of production tools and influence the need for heat treatment.

Companies are also specializing in the heat treatment of new steels and application of coatings. This results in some heat treatment processes no longer being performed in tool shops.

Related Components

All components apply.

Tools and Equipment

Heat treating equipment, measuring tools, PPE and safety equipment.

Task 13 Heat treats materials.

Required Knowledge

• K 1 types of heating mediums such as gas, electric and vacuum furnaces, and gas torches
• K 2 composition of material
• K 3 effect of heat on the properties of materials
• K 4 quenching media and procedures
• K 5 heat treatment procedures and outcomes
• K 6 heat treatment specifications
• K 7 heat treatment materials and equipment
• K 8 metal cleaning processes

Sub-task - D-13.01 Selects heat treating process.

Key Competencies

• D-13.01.01 identify heat treating procedure and equipment based on material application and characteristics according to part specifications and requirements
• D-13.01.02 verify suitability and availability of heat treatment equipment to confirm feasibility of chosen procedure

Sub-task - D-13.02 Hardens materials.

Key Competencies

• D-13.02.01 set furnace cycle or torch settings according to material specifications
• D-13.02.02 ensure part is prepared and cleaned
• D-13.02.03 check quenching media temperature using tools such as thermometers and infrared scopes to ensure it is at room temperature or cooler
• D-13.02.04 move quenching media to proximity of furnace if required to reduce heat loss of part
• D-13.02.05 ensure part is heated to the specified temperature and held in the oven to reach the specific condition
• D-13.02.06 submerge and agitate part in quenching media to achieve hardness
• D-13.02.07 remove part from quenching media when suitable temperature is attained
• D-13.02.08 clean part to remove oil and scale using methods such as polishing, sandblasting, ultrasonic cleaning and de-scaling

Sub-task - D-13.03 Tempers materials.

Key Competencies

• D-13.03.01 set furnace cycle or torch settings according to material specifications
• D-13.03.02 ensure part is prepared and cleaned
• D-13.03.03 ensure part is heated to set temperature according to tempering specifications to reach specified condition
• D-13.03.04 confirm specified temperature is reached using equipment such as temperature sticks and colouring charts as required

Sub-task - D-13.04 Anneals materials.

Key Competencies

• D-13.04.01 set furnace cycle according to material specifications
• D-13.04.02 clean part to remove oil prior to heating process
• D-13.04.03 ensure part is heated to set temperature according to annealing specifications to reach specified condition
• D-13.04.04 control cool down rate according to material requirements following the annealing procedures

Sub-task - D-13.05 Normalizes materials.

Key Competencies

• D-13.05.01 set furnace cycle according to material specifications
• D-13.05.02 clean part to remove oil prior to heating process
• D-13.05.03 ensure part is heated to set temperature according to normalizing specifications to reach specified condition
• D-13.05.04 control cool down rate according to material requirements following the normalizing procedures

Sub-task - D-13.06 Carburizes materials.

Key Competencies

• D-13.06.01 set furnace cycle or torch settings according to material specifications
• D-13.06.02 ensure part is prepared and cleaned
• D-13.06.03 ensure part is heated to set temperature according to case hardening specifications to reach specified condition
• D-13.06.04 place part into carburizing material such as carbon powder to completely cover the part
• D-13.06.05 check quenching media temperature using tools such as thermometers and infrared scopes to ensure it is at room temperature or cooler
• D-13.06.06 move quenching media to proximity of furnace if required to reduce heat loss of part
• D-13.06.07 submerge and agitate part in quenching media to achieve hardness
• D-13.06.08 remove part from quenching media when suitable temperature is attained
• D-13.06.09 clean part to remove oil and scale using methods such as polishing, sandblasting, ultrasonic cleaning and de-scaling

Task 14 Tests heat treated materials.

Required Knowledge

• K 1 hardness testers such as Rockwell and Brinell
• K 2 visual testing materials such as dye penetrant and magnifiers
• K 3 hardness scales, quality conditions and specifications

Sub-task - D-14.01 Performs visual inspection.

Key Competencies

• D-14.01.01 select and use tools and equipment such as magnifiers, dye penetrant and microscopes
• D-14.01.02 prepare workpiece surface by cleaning and removing oxidization
• D-14.01.03 identify surface imperfections such as scratches, cracks and craters
• D-14.01.04 identify geometric deformations and distortions

Sub-task - D-14.02 Performs hardness test.

Key Competencies

• D-14.02.01 select and use tools and equipment such as hardness testers, charts, indenters and V-blocks
• D-14.02.02 prepare workpiece surface by cleaning and removing oxidization
• D-14.02.03 verify hardness tester is functioning properly by using standard calibration samples
• D-14.02.04 set up workpiece on hardness tester by aligning with indenter
• D-14.02.05 activate mechanisms to initiate hardness test
• D-14.02.06 read test value displayed and compare with specifications
• D-14.02.07 record values for quality assurance