Method and condition
Send the standard or customer procedure, temperature, RH, duration and pressure basis.
HAST test chamber
An unsaturated high-pressure temperature and humidity chamber for accelerated moisture-reliability testing of semiconductor packages and electronic components.
MODELSDX-HAST350 / DX-HAST450
INTERNAL CHAMBERφ300 × D450 / φ400 × D550 mm
TEMPERATURE & HUMIDITY+100 to +143°C / 65% to 100% RH
NORMAL WORKING PRESSUREUp to 0.294 MPa gauge
Bias terminals, a +155°C high-temperature configuration and test-specific fixtures are available after method and specimen review.
Recommendation
Product Details
IMAGE PLACEHOLDER — Replace with real DX-HAST350 / DX-HAST450 product and open-door photos
UNSATURATED PRESSURE AGING
Select a HAST test chamber from the method, specimens and bias—not pressure alone.
Dexiang DX-HAST350 and DX-HAST450 chambers combine +100 to +143°C, 65% to 100% RH and controlled pressurized moisture to accelerate reliability evaluation of semiconductor packages and electronic components. Before quotation, match the chamber to the exact HAST condition, specimen envelope, loading quantity and electrical-bias plan.
Specimen envelope
Provide dimensions, quantity, orientation, fixture and clearance around the cylindrical workspace.
Bias requirement
Define voltage, current, pins, insulation, channel grouping and failure monitoring.
Acceptance evidence
State calibration, pressure documentation, FAT records and destination requirements.
CONTROL THE COMPLETE CYCLE
Valid HAST exposure depends on more than reaching the setpoint.
Ramp sequencing, steam generation, specimen temperature, exposure timing, controlled cooling and pressure release all affect repeatability. Releasing pressure too early or cooling too quickly can cause unwanted condensation or pressure shock.
Standard range: +100 to +143°C and 65% to 100% RH. +155°C is a custom high-temperature option.
Normal working gauge pressure 0.294 MPa; safety valve 0.343 MPa; maximum allowable pressure and rupture disc 0.392 MPa.
Define whether dwell time begins after temperature, RH and pressure stabilize at the agreed reference point.
Program warm-up, specimen preheating and controlled cool-down to protect method intent and reduce unintended wetting.
Configure feedthroughs, insulation, voltage/current limits, channel isolation and interruption response.
Confirm water quality, shelf material, fixture compatibility, spacing and usable—not nominal—workspace.
Pressure values are gauge pressure unless the signed specification states otherwise. Final pressure-vessel nameplate, relief settings and destination compliance documentation control the delivered equipment.
APPLICATIONS AND FAILURE MECHANISMS
Accelerate moisture stress while preserving the intended failure mechanism.
HAST is commonly used for non-hermetic semiconductor packages, ICs, PCB assemblies, connectors, sensors, encapsulants and other moisture-sensitive electronic parts. The test can accelerate moisture ingress and associated degradation, but the chamber does not by itself identify root cause or predict a universal number of service years.
Investigate moisture-related delamination, interfacial degradation, corrosion, leakage and insulation resistance change.
Stress conductors, coatings, solder interfaces and insulation systems with fixtures and bias designed for the board.
Evaluate moisture resistance and seal performance without exceeding material limits unless overstress is deliberate.
Support comparison of adhesion, swelling or other material change using a defined downstream measurement.
Apply electrical bias only with reviewed pin spacing, isolation, current limits and failure-detection logic.
Use electrical, cross-section, microscopy, adhesion or other prescribed checks before and after exposure.
IMAGE PLACEHOLDER — Replace with real chamber interior, shelves, controller and pressure-safety photos
MODEL SELECTION
Choose chamber diameter and depth from the loaded fixture envelope.
The cylindrical chamber dimensions—not a calculated litre label—are used for model selection. Confirm tray clearance, specimen spacing, wiring bend radius and service access before order.
| Specification | DX-HAST350 | DX-HAST450 |
|---|---|---|
| Internal chamber | φ300 × D450 mm | φ400 × D550 mm |
| Temperature | +100 to +143°C; +155°C custom option | |
| Humidity | 65% to 100% RH adjustable | |
| Normal working pressure | 0.294 MPa gauge | |
| Maximum allowable pressure | 0.392 MPa gauge | |
| Temperature fluctuation | ≤ ±0.5°C | |
| Temperature deviation / uniformity | ≤ ±2°C deviation; typical uniformity to be confirmed in the agreed test condition | |
| Humidity fluctuation | ≤ ±2% RH; distribution/condition to be confirmed | |
| Power | 220 V, single phase, 4 kW | 220 V, single phase, 5.5 kW |
| Approx. exterior / weight | 750 × 900 × 1700 mm; 250 kg | 830 × 800 × 1640 mm; 300 kg |
| Interface | USB and RS-485/RS-232; RJ45 by configuration | |
| Bias terminals | Configured after voltage, current, pins, isolation and monitoring review | |
Approximate exterior dimensions and weight must be checked against the final Dexiang drawing. Standard accessories and options are controlled by the signed technical agreement.
TEST ROUTE BOUNDARIES
HAST is not a generic name for every accelerated reliability test.
Use the prescribed moisture state and stress mechanism. Substituting another chamber simply because it is “accelerated” can change the failure mechanism and invalidate correlation.
HAST / UHAST / BHAST
Pressurized damp heat above 100°C with controlled unsaturated humidity. BHAST adds electrical bias and requires engineered terminals, insulation and monitoring.
PCT
Saturated steam pressure-cooker exposure at 100% RH. It belongs on the separate PCT product page and is not interchangeable with unsaturated HAST.
85°C / 85% RH
Below-boiling damp heat at atmospheric pressure. It generally takes longer and needs a conventional temperature-humidity chamber.
HALT / HASS
Rapid thermal change and multi-axis vibration for design-limit discovery or screening. It requires different equipment.
METHOD REVIEW
Review the chamber against the exact standard edition and specimen plan.
Dexiang can configure the system to support applicable HAST procedures. Equipment capability alone does not establish test conformity; specimen preparation, preconditioning, bias circuit, ramp, dwell, water quality, measurement and acceptance criteria also matter.
REQUEST A USEFUL PROPOSAL
Send eight inputs for model and bias-terminal review.
- 1
Method
Standard/customer procedure and revision.
- 2
Setpoints
Temperature, RH, pressure basis and time.
- 3
Specimens
Drawing, quantity, mass and orientation.
- 4
Fixture
Tray, holder, materials and clearance.
- 5
Bias
Voltage, current, pins and monitoring.
- 6
Throughput
Loads per run and runs per week.
- 7
Utilities
Country voltage, drainage and access.
- 8
Evidence
FAT, calibration and pressure documents.
Typical delivery is about 20–30 days; non-standard configurations may require 30–45 days. Final timing follows the approved specification and order schedule.
FAQ
HAST test chamber questions
What is a HAST test chamber used for?
It exposes moisture-sensitive electronic specimens to controlled temperature, humidity and pressure above normal boiling conditions to accelerate moisture-related reliability evaluation.
What is the difference between HAST, UHAST and BHAST?
UHAST is unbiased exposure. BHAST applies electrical bias during exposure. “HAST” is often used as the broader method name, so the proposal must state whether bias terminals and monitoring are required.
Which model should I choose?
Choose DX-HAST350 or DX-HAST450 from the loaded specimen and fixture envelope, wiring clearance, bias-pin count and required throughput—not model number alone.
Can this chamber perform PCT?
This product page is specified for controlled HAST conditions. If your method requires saturated steam at 100% RH, request the PCT configuration review instead of assuming interchangeability.
Why do cooling and exhaust modes matter?
Cooling too quickly or releasing pressure prematurely can create unintended condensation or pressure shock. Agree the end-of-test sequence with the method and specimen risk.
Is external cooling water required?
The standard proposal is reviewed for self-contained steam generation and air/passive cooling. Confirm site utilities and any special cooling option in the final technical agreement.
What water should be used?
Use the water quality stated in the method and operating manual. Water purity and chamber cleanliness can affect contamination, deposits and repeatability.
Are bias terminals standard?
Terminal quantity and rating are configured after review of voltage, current, pins, insulation, grouping and monitoring. Do not select terminals by pin count alone.
What documentation can be requested?
Specify calibration scope, FAT records, pressure-vessel documentation, manuals, electrical drawings and destination-language requirements before quotation.
Does HAST time directly equal years of field life?
No universal conversion applies. Acceleration depends on the material, stress condition and failure mechanism; excessive stress may activate a different mechanism.
HAST CONFIGURATION REVIEW
Get the right chamber, fixture and bias-terminal plan before quotation.
Send your HAST method, target condition, specimen drawing, quantity, fixture and electrical-bias requirement. Dexiang will review DX-HAST350 versus DX-HAST450 and return a method-matched proposal.
Dexiang｜ Instruments
As a high-tech manufacturer, we integrate R&D, design, production, and sales under one roof. Our philosophy—"Quality Ensures Survival, Integrity Drives Development, and Management Yields Efficiency"—is woven into every product we build. We continuously assimilate cutting-edge global technologies and refine our practices through years of hands-on experience.
